BRPI0900810B1 - CUTTING MACHINE AND CUTTING METHOD OF STEM SEGMENTS FROM A GRASS PLANT - Google Patents

Abstract

cutting machine and method of cutting stem segments from a grass plant. the present invention relates, in general, to a cutting machine for cutting stem segments with desired characteristics. the present invention is particularly useful for cutting stem segments of grassy plants (of the gram grasselpoaceae family), such as saccha rum spp plants, including sugar cane. according to an embodiment of the present invention, the cutting machine comprises a sensor for identifying at least one characteristic of the stem, means for placing the stem in a certain cutting position, depending on the response of said sensor, and means for cutting the stem; wherein said sensor identifies at least one characteristic of the stem, said medium places the stem in a given position and said cutting means of the stem are interconnected and controlled by a control means to cut the stem in a specific position, depending the presence of the mentioned characteristic identified; characterized by the fact that the sensor is selected from the group consisting of a pressure transducer sensor, a capacitive sensor, an ultrasound sensor, an x-ray sensor, a magnetic sensor and a microwave sensor.

Description

"CUTTING MACHINE AND METHOD FOR CUTTING STEM SEGMENTS FROM A GRASS PLANT" Field of the Invention The present invention relates, in general, to a cutting machine and, more specifically, the present invention relates to a machine cutting stem segments with desired characteristics. The present invention is particularly useful for cutting segments of stems of grassy plants (of the Gramineae / Poaceae family), such as Saccharum spp plants, including sugar cane. _____The present invention also relates to a method of cutting stems from these plants that comprises a desired characteristic.

Definitions For the descriptive report below and attached claims, the following definitions are used: Stem: stem or stem of the stem part of a grassy plant, that is, the main trunk of a plant, specifically the primary axis of a plant that develops buds and buds.

Stake: segment, section or cut of stem containing one or more nodes. Node: location on the stem where the bud or bud is formed on a grassy plant.

Bud or bud: embryo, spore or germ of a grassy plant.

Germinate / germination: emergence of a new plant from a button.

Background of the Invention Graminaceous plants (from the Gramineae / Poaceae family) are usually formed by a stem that comprises several nodes and internals along its length. The knot comprises the bud (or bud) of the plant, which can be used to generate a new plant, such as for a harvest.

Examples of grassy plants include bamboos (Bambusoideae, such as PhyUostachys spp and Arundinaría spp), sugar cane (Saccharum spp) and grasses (such as elephant grass, Pennisetum purpureum).

In the case of sugar cane, in particular, the media has given prominence to it as an alternative to fossil fuels, since the alcohol obtained through the fermentation of these plants is apparently the promise of a clean and renewable fuel. The area of sugar cane plantation is growing worldwide, as well as investments in factories producing alcohol. The sugar cane seed is a dry fruit with a seed or karyopsis formed from a single carpel, in which the wall of the ovary (pericarp) is joined to the lining of the mind (forehead). The seeds are oval, yellowish brown and very small, about 1 mm long. Sugarcane seed only germinates, however, under specific environmental characteristics, such as constant heat and humid climatic conditions. These climatic conditions are not found everywhere where sugar cane is grown and, therefore, the germination of sugar cane seed is not always guaranteed. For commercial agriculture, the sugar cane seed is not cultivated, but the cane is propagated vegetatively by planting a stem segment (or part of a stem, stem or seedling). As mentioned above, the sugar cane stem, as well as the stem of grassy plants, comprises several nodes, from which new plants grow. The traditional process of planting sugar cane involves reserving an area of the harvest to be used as a source of plants for replanting, as the nodes are included in the stem. The plants used for replanting are harvested and then cut into segments of about 20 to 50 cm, so that at least two nodes are present in each stem segment (stake). It is necessary to cut the seeds to break the apical dominance, which otherwise causes poor germination when using full-length (uncut) stems. The segments are cut to have at least two buds to guarantee germination, as not every bud germinates. The current machines used to cut sugar cane segments are not able to identify any characteristics of the stem and, therefore, the precise position of the cutting locations is determined at random.

After cutting, the cuttings are laid horizontally, on top of each other, in holes in the plowed soil, which are generally wide at ground level, deep (40 to 50 cm wide and 30 to 40 cm deep) and lightly covered with solo then.

Although this planting method is still being used today, the entire process is relatively inefficient, as many stem segments, each with two to four knots, need to be used to guarantee germination. The consequence is that a large replanting area needs to be used and, therefore, the area that could be used for the harvest and production of alcohol or sugar needs to be reserved for replanting. There is a need, therefore, to increase the yield of the sugar cane planting technique.

With the current technique, the sugar cane stems are cut randomly, usually to a length of about 20 cm to 50 cm, a length that guarantees to comprise two to four knots. This is because the buttons do not emerge on all nodes. It has been found, however, that when treated with certain fertilizers and other compounds before planting, the germination of a bud is possible from a short section of stem that has a single knot.

Additionally, the random cut of the stem can damage the knots and buttons, or the knots can be very close to the end of the segment, preventing the germination of a button from that node. - - In addition, the random cut does not identify other specific characteristics of the stem, such as damaged, diseased or deteriorated stem segments that can affect bud germination.

Consequently, it is desired to increase the efficiency of planting and germination of grass plants, especially sugar cane, reducing the number of nodes in each stem segment and also avoiding damage to the nodes during cutting. It is also desirable to identify certain characteristics of the stem, avoiding the planting of buds or injured segments, including stems that are damaged, diseased or deteriorated, in order to increase the germination efficiency of the plants.

Although cutting the stem with a reduced number of knots and without damage can be done manually, productivity would be small and / or it would be necessary to employ a large number of people just to cut the stems, which naturally increases the costs of the planting process .

Therefore, it is also desirable to provide a controlled and automatic apparatus and method of cutting the rods into segments with desired characteristics and, in particular, of cutting a rod segment comprising a single knot without damaging the button.

It is also desirable to provide a controlled and automated apparatus and method for identifying certain characteristics of the stem, such as the presence of diseases and pests, and / or knots that are injured so that a viable button will not develop.

Published Japanese Patent Applications No. 1991-251104 and 2003-038017 relate to cutting devices for plants using vision based sensing technology. These optical sensors are problematic, especially for cutting grass plants for several reasons. Firstly, leaf material along the stem of grassy plants hides the location of the nodes and, therefore, the use of a vision-based sensor would require thorough cleaning of the stem to remove all leaf tissue prior to verification. The process of cleaning the rods takes time and can damage the buds that develop in the nodes. Second, the cutting environment is dirty, due to the presence of dust from the cut and sap from the cut rods, which can obscure the vision sensors and generate slow or inaccurate node verification.

Detailed Description of the Invention To achieve the objectives mentioned above, among others, a cutting machine is proposed, particularly a cutting machine for stem segments of a grass plant, which comprises a sensor to identify at least one characteristic of the stem, means placing the stem in a certain cutting position, depending on the response of said sensor, and cutting means of the stem; wherein said sensor identifies at least one characteristic of the stem, said medium places the stem in a certain position and said cutting means of the stem are interconnected and controlled by a control means to cut the stem in a specific position, depending the presence of the mentioned characteristic identified; characterized by the fact that the sensor is selected from the group consisting of a pressure transducer sensor, a capacitive sensor, an ultrasound sensor, an X-ray sensor, a magnetic sensor and a microwave sensor.

The following characteristics, alone or in combination, can also be understood in the present invention: The mentioned rod is cut to a previously determined length. The mentioned stem is a Saccharum spp stem, also known generally as sugar cane .------------- The mentioned stem is a stem of a Bambusoideae plant, such as bamboo. The aforementioned stem is an elephant grass plant stem (Pennisetum purpureum). ________- The aforementioned sensor for identifying a minus one characteristic of the rod is a pressure transducer sensor, a capacitive sensor, an ultrasound sensor, an X-ray sensor, a magnetic sensor or a microwave sensor. The said sensor comprises at least two metal surfaces through which the sugar cane passes, the distance between which may vary, depending on the diameter of the stem.

The surfaces can assume any conformation, such as plates, bars, blocks, discs, cylinders or similar.

Optionally, the metal surfaces can apply pressure to the stem as it passes between them, so that the stem touches the two surfaces. Said pressure can be applied by any appropriate mechanism, such as springs, compressed air, hydraulic pressure or the like.

In one embodiment, said surfaces can be in the form of cylinders.

Optionally, at least one of the aforementioned cylinders has a frustoconical shape.

In one embodiment, said magnetic sensor is an electromagnetic sensor.

In one embodiment, said sensor may be an electromagnetic sensor comprising two metallic cylinders between which the sugar cane rod passes, wherein said cylinders apply pressure to the rod as it passes between them.

In an alternative embodiment, the sensor may be an electromagnetic sensor comprising a cylindrical body and a series of metal electrodes made of thin metal plates that generate the electromagnetic field, in which the plates are arranged at one end in regular spaces in around the perimeter of said cylindrical body and, at the other ends of the said plates, have free ends to allow the passage of the stem through them.

Optionally, water is applied to the stem before passing through the sensor. Said cutting medium is one or more of a knife, circular knife, reaper, circular saw, plasma cutting system, laser cutting system, cutting in high pressure water (optionally comprising abrasive media), marking device or cutting device. Said rod cutting means comprise two knives spaced apart at a predetermined distance. The mentioned means of placing the rod in a determined position for cutting is one or more among: rotating pulleys, conductive belt, conductive chain, one or more clamps or rollers, directed by appropriate means. The aforementioned characteristic identified on the stem is the position of a node on the stem. The mentioned characteristic identified in the nail is the injury. The mentioned characteristic identified in the stem in the presence of disease or pests. - The mentioned feature identified in the stem is a deteriorated segment. The mentioned control means is a Programmable Logic Circuit (PLC) system or Computerized Numerical Control (CNC) system, which, in turn, controls the cutting machine to cut the shank with the desired characteristic, depending on the reaction of the mentioned means identification of at least one characteristic of the stem. Said sensor comprises a set of generation of a digital emission for said means of control. Said set comprises a frequency generator; a configuration transformer; a frequency filter; a signal amplifier; a programmable digital processor; and a digital emission, when using an electromagnetic sensor. The mentioned machine can cut several rods substantially simultaneously. The mentioned machine can cut a single rod in several positions substantially simultaneously.

The aforementioned means of placing the rod in a given position are replaced by means of placing the cutting means in the cutting position with respect to the rod.

When an unwanted feature is identified on the stem, it is discarded and not cut. Said length is in the range of about 2 to about 12 cm, suitably about 3 to about 8 cm, more suitably about 3.5 to about 4.5 cm, and particularly about 4 cm. The present invention also describes a method of cutting rods using a machine as described above. ---- Brief Description of the Figures The present invention will now be described with respect to a specific embodiment with reference to the attached figures, in which: Figure 1 shows a schematic cross-sectional side view of a cutting machine according to an embodiment of the present invention; Figure 2 is a schematic perspective view of the cutting machine of Figure 1; Figure 3 is a block diagram showing an example of a sensor assembly; Figures 4a, 4b and 4c illustrate the rear, side and front view of a sensor according to an embodiment of the present invention; Figures 5 to 7 are graphs that demonstrate the identification of a characteristic on the stem; Figure 8 illustrates an electromagnetic sensor according to a specific embodiment of the present invention; and Figure 9 is a schematic illustration of a stem, particularly a sugar cane stem, which passes through the electromagnetic sensor according to the present invention.

Detailed Description of the Invention The cutting machine (10) according to the present invention is represented schematically in Figures 1 and 2. The figures describe a specific and example embodiment of the machine according to the present invention, which is used to identify and cut sugar cane stem segments. The machine according to the present invention is intended for cutting stem segments (piles) that comprise at least one feature, by controlled and automated means - The machine according to the present invention is particularly useful for cutting stem segments of grassy plants, particularly Saccharum spp, such as sugar cane. A characteristic of the stem segment is, for example, a knot comprising a button. ____ As mentioned above, it was noted that when a segment comprising a node is treated with certain compounds and / or fertilizers, it can be planted to grow a new plant. Consequently, it may be desirable to cut the stems into segments that comprise only one node, in order to increase the efficiency of the planting method, particularly the planting of sugar cane. The stem segments can be cut to contain at least one node. Suitably, the stem is cut so that each stem segment contains only one node.

Alternatively, it may not be desirable that some characteristics are included in the stem or stem segments for planting, such as the presence of lesions, diseases, pests or deteriorated segments. In this case, the stem segment will not be used, but will be discarded. The embodiment shown in Figures 1 and 2 illustrates the machine comprising means for identifying at least one characteristic of the stem, such as a sensor (24); means (60, 61) for placing the rod in the cutting position; means (51, 52) for cutting the stem into a segment; and control means (30) that control the cutting position of the shank (40) to obtain a segment (41) with a terminated length (L) and a desired characteristic, depending on the reaction of the identification means (24). In particular, the feature is a knot (42) in the stem. The sensor to identify at least one characteristic of the rod is selected from the group consisting of a pressure transducer sensor, capacitive sensor, ultrasound sensor, X-ray sensor, microwave sensor and magnetic sensor. In one embodiment, the sensor is selected from the group consisting of an X-ray sensor, magnetic sensor and microwave sensor. In another embodiment, the sensor is an X-ray or magnetic sensor. In one embodiment, the sensor is a microwave sensor. In another embodiment, the sensor is an X-ray sensor. In another embodiment, the sensor is a magnetic sensor. Suitably, the magnetic sensor is an electromagnetic sensor. According to the described embodiment, the sensor (24) used to identify a specific characteristic on the rod is an electromagnetic sensor.

In the case of electromagnetic sensors and as known to those skilled in the art, different materials or elements cause different reactions to electromagnetic waves in an electromagnetic field. The electromagnetic waves reflected by a certain material can be transformed into a wave pattern that allows the identification of a certain characteristic of the material. This is the principle of electromagnetic resonance machines used in diagnosing internal tissues of the human body, for example.

Using an electromagnetic sensor, the frequency of magnetic resonance is measured between two metal surfaces and the frequency is interpreted by a transducer. Particularly with sugar cane, the knot is more rigid and comprises less water than the average stiffness and water content of the rest of the stem. A node can be identified, therefore, using an electromagnetic field, as its lower water concentration and higher rigidity (fiber content) will cause a different electromagnetic wave reaction with respect to the rest of the rod. Damaged, diseased or damaged stem sections can also be detected, as these also exhibit a different water and fiber content compared to the rest of the stem .------- ----------- ------------ -------------- Suitably, the sensor comprises at least two metal surfaces between which the sugar cane rod passes. The distance between the surfaces can vary to accommodate variations in the stem diameter. The surfaces can assume any conformation, such as plates, bars, blocks, discs, cylinders or similar. Optionally, the surfaces can apply pressure to the stem as it passes between them, so that the stem touches the two surfaces. This facilitates the detection of the node; if, for example, a pressure sensor is used, the slight movement of one or both surfaces will be detected when a knot passes between them, as the diameter of the stem is slightly wider at the position of a knot, which protrudes slightly at from the rest of the stem. Pressure can be applied by any appropriate mechanism, such as springs, compressed air, hydraulic pressure or the like. In one embodiment, said surfaces can be in the form of cylinders. Optionally, at least one of the aforementioned cylinders has a frustoconical shape to facilitate the entry of the sugar cane stem into the sensor unit and to align it between the surfaces.

In one embodiment, water is applied to the stem, such as by spraying or passing through a water bath, prior to verification (such as before the passage of the stem through the sensor device). This increases electrical conductivity and therefore increases signal strength by up to 50%. This allows for faster and more accurate verification of the stem characteristic.

The control means (30) must interpret the information sent by the sensor to perform the combined action of controlled and automatic cutting. These control means (30) can be, for example, a Programmable Logic Circuit (PLC) or a Computer Numerical Control (CNC) system, which receives a digital signal with specific digital data that will lead to the control of the cutting machine, such as will be explained in more detail below.

The cultivation media can be any appropriate means of cutting a stem, particularly a sugar cane stem, such as, but not limited to, a knife, circular knife, reaper, gulhotina, circular saw, marking means, means cutting device, or a high pressure water cutting device (optionally comprising abrasive media, such as sand). Other non-mechanical means can also be employed, such as plasma cutting and laser cutting systems.

According to the embodiment shown in the figures, a circular knife and, in particular, two circular knives (51, 52) spaced apart in a previously determined length (L) are used. The knives can act simultaneously to increase the cutting productivity, that is, the cutting of shank segments to the determined length can be carried out in a single cutting step.

Although not displayed, the knives are operated properly. The drive of the knives can be achieved by any appropriate means of detection, such as pneumatic cylinders, hydraulic cylinders or servomotors, as is well known to those skilled in the art.

The means of placing the stem in an appropriate position for cutting may be suitable means of controllable direction of the stem, to obtain a segment (41) of the stem cut with a desired characteristic. These means can be, for example, rotating pulleys, chains or conductive belts, directed by appropriate means such as servomotors, steam or hydraulic motors to controllably steer the rod in a determined position, either vertically or horizontally.

As described in the present embodiment, two rotating pulleys (60—6T) driven by servo motors (not shown) are used ^ The pulleys are spaced apart at a certain distance, in order to fix the rod and direct it at a distance determined for placement in the cutting position.

As mentioned above, any sensor can be used to detect a characteristic of the sugar cane stem and the description below with respect to a specific realization will consider an electromagnetic sensor.

In this specific embodiment of the present invention, the electromagnetic sensor is the one illustrated schematically in Figure 8. Due to the variable physical characteristics of the sugar cane, particularly the variations in the length and diameter of the stem (the sugar cane stems are rarely rectilinear), proved it is shown that the use of a sensor described in the present embodiment is efficient in detecting a desired stem characteristic. The electromagnetic sensor (24) is formed by two metallic cylinders (245, 246) between which the sugar cane rod (40) passes. The cylinders rotate around their central axes, which are fixed to means that allow variation with respect to the distance (D) between them. The variation in the distance (D) between the cylinders will therefore allow the passage of sugar cane stems (40) with different diameters. At the same time, the medium that secures the cylinders and allows the distance between them to vary also applies pressure to the sugar cane stem as it passes through the sensor. The pressure applied to the stem facilitates the detection of the location of the node (42) on the stem. The means that fixes the cylinders and allows the variation of the distance between them, while applying a certain pressure on the rod, can be, for example, but without being limited to coil springs (243, 244), springs, cylinders with compressed air or cylinders with hydraulic pressure, among others, one or both cylinders may have a frustoconical shape (246), in order to facilitate the entry of the sugar cane stem into the sensor, as there may be variations in the stem diameter. The metallic alloy of the cylinders can be of any metallic material suitable to generate an electric field and, consequently, an electromagnetic field, such as steel, stainless steel, aluminum, copper, nickel, bronze or their mixtures or alloys. Bronze is particularly used.

When the sugar cane node passes between the cylinders, there is a small variation in the reaction of the electromagnetic wave, which can be detected and used to identify the position of the node on the stem.

To generate a digital data transmission (which will be used by a PLC or CNC to control the machine), depending on the response of the sensor reading, the sensor (24) is connected to a set (20) that has the function of generating the electromagnetic field and also collect and interpret the data generated by reading the sensor.

An example of a sensor set (20) is represented schematically in Figure 3. As those skilled in the art will appreciate, this sensor set is an example of realization and many variations can be developed to produce digital data depending on the sensor reading.

This set according to the present example comprises a frequency generator (21), a transformer (22), a frequency filter (23), a signal amplifier (25), a programmable digital processor (26) and a digital broadcast (27). The high frequency generator (21) can be any appropriate means of generating a high frequency sine wave capable of producing an electric field and, consequently, a magnetic field in the sensor, as will be explained in more detail below. The sine wave can be an alternating electric current, which preferably has a relatively high voltage and low current. The current and voltage can be determined empirically by the technicians in the subject, depending on the reaction of the electromagnetic waves to the characteristics of the sugar cane stem that you want to identify.

As electrical frequency generators (21) normally produce a relatively low voltage, a configuration transformer (22) can also optionally be used after the frequency generator in order to increase the voltage.

It has been observed that a voltage of about 10 to about 2000 Vpp (volts peak to peak), particularly about 50 to about 1500 Vpp and, more specifically, about 150 Vpp is appropriate to produce an electromagnetic field in the sensor for identify a characteristic of the stem. It has also been proven that the current defined in a range of about 50 to about 500 mA (milliamps), particularly about 100 to about 250 mA and, more particularly, about 200 mA, is suitable for identifying a characteristic on the stem . The frequency used in the generator can also be determined by those skilled in the art and, according to this embodiment, an appropriate frequency is defined between about 800 kHz and about 7.2 MHz, particularly about 1 MHz to about 3 MHz and, more particularly around 2 MHz.

These ranges are examples and the voltage, current and frequency can be determined empirically by the technicians in the subject, depending on the type of rod of the characteristics to be identified. The configuration transformer (22), as mentioned above, can be used to increase the voltage produced by the frequency generator. The transformer can increase the voltage as necessary to achieve the desired voltage, depending on the voltage emission of the generator. The transformer can increase the voltage by up to twenty times and, more particularly, about fifteen times if the signal generated by the high frequency generator has about 10 Vpp. The amplified signal at the output of the transformer will have about 150 Vpp, considering the ranges mentioned above.

As those skilled in the art can understand, the transformer can be suppressed if the current and voltage generated by the generator are appropriate for the purpose of creating a detectable electromagnetic field in the sensor, particularly within the voltage, current and frequency ranges exemplified above. The signal from the generator and transformer is injected into a frequency filter (23), whose function, as the technicians in the subject will appreciate, is to identify the variation of the electromagnetic waves generated and detected by the sensor. Figure 5 illustrates an example of a signal that can be detected by the sensor (24) and separated in the filter (23). This graph shows the variation of the signal voltage over time, when a stem, particularly a sugar cane stem, is passing through the sensor (24). In you, there is no rod in the sensor and the Vo voltage is higher. When the rod starts to pass through the sensor, the voltage drops (Vi in t2) and the knot, which contains less water than the average water content of the rod and is more rigid, causes a disturbance in the wave, which can be detected in t3. After the node passes, the signal stabilizes in L and the voltage increases again when the rod leaves the sensor (24) in ts.

This example of a wave pattern has been described with respect to a stem comprising only one node. As the technicians in the subject will appreciate, as the stem can comprise several nodes, the pattern t2 to t3 will be repeated until the end of the stem, ending at t5.

After separating the signal exemplified in Figure 5 in the filter (23), —wave pattern is amplified in the ~ amplifier- (25) ^ and inverted into an analog derived signal (Figure 6) and converted into a digital signal to generate an emission of digital data (Figure 7) (see also reference 27 and Figure 3). The digital data emission (27) is generated by a programmable processor (26), which is used to interpret the analog signal, convert it into a digital signal to produce a digital data representative of a characteristic of the stem that you want to identify, such as the node in this comparative example. The digital data transmission (27) is connected to a PLC or CNC (30), which coordinates the targeting means and the cutting means of the machine to cut the rod in the desired location. As technicians in the subject can appreciate, both the PLC and the CNC are programmable systems to perform certain coordinated operations on a machine, depending on the digital signal emission from the sensor set. After the digital signal (represented in Figure 7) is output to PLC or CNC, the exact location of the node on the stem is identified and the PLC or CNC directs the means of directing the stem for correct placement for cutting, as described below.

In a specific embodiment of the machine, the electromagnetic sensor can be the one described schematically in Figures 4a to 4c. Due to the variable physical characteristics of sugar cane, particularly the variations in stem length and diameter, since it is rarely straight, it has been proven that the use of a sensor is efficient in detecting a desired stem characteristic. The electromagnetic sensor, according to this specific realization, has a body (241) with a cylindrical shape and is formed by a series of metallic electrodes, elaborated with thin metallic plates (242) that generate the electromagnetic field. The electrodes are fixed at one end in regular spaces around the perimeter of the cylindrical body (241), which is preferably made of insulating material (such as a polymer) to avoid interference with the electromagnetic field, while the other end of the electrodes has ends that will allow the sugar cane stem to pass through. The sensor employed can also be an X-ray or microwave sensor, in which these sensors will have different reactions with respect to specific characteristics along the length of the rod. The X-ray sensor can detect, for example, a different type or concentration of organic tissues in the node. The microwave sensor may have a different reaction due to the lower water concentration in the node, as microwaves react to water molecules.

As the technicians in the subject can appreciate, the sensor set will also have a different configuration depending on the type of sensor used. If X-ray or microwave sensors are used, for example, a variation of the X-ray field or the microwave field may react to the digital signal generation for PLC or CNC, which indicates the characteristic of the rod that want to detect, just like the node. The operation of the sugar cane cutting machine is now explained according to the explanatory realization. The sugar cane stem (40) is inserted into the sensor (24), directed by the rotating pulleys (60, 61) that secure the stem and direct it through the sensor. Alternatively, other targeting means can be employed such as conductors in which the sugar cane rod rests on a conveyor belt and passes through the sensor. After the introduction of the stem into the sensor, the latter identifies the introduction of the stem and the disturbance of the electromagnetic signal indicates the location of the node (42) in the stem, as explained above. After identifying the location of the node on the stem by the sensor, the sugar cane stem is additionally directed to a distance previously determined by the pulleys or conductor, so that the button is placed approximately in the middle of the desired cut length (L) between the knives (51, 52). The rod then stops in that position and the knives are activated to make the cut. The sugar cane stem segment (41) with a desired length (L) is obtained and contains a single node (42) in its intermediate part and any sections between nodes left behind (43) are discarded or reused, for example, for animal feed.

After cutting, the knives (51, 52) are reset, another button will be identified by the sensor (24) and the pulleys or the conductor will place the next segment for cutting. The process is repeated until the end of the stem and another stem restarts the entire process.

As those skilled in the art will appreciate, the length (L) of the segment (41) that will be cut may vary according to specific needs, such as the type of sugar cane or the desired length of the segment that has been shown to be long enough to allow the bud to germinate. It has been observed that a length of about 2 to about 12 cm, particularly about 3 to 8 cm, more particularly about 3.5 to 4.5 cm, preferably about 4 cm, is appropriate to ensure germination of the bud , when a node (42) is comprised in segment (41). The exact length of the segment is not critical and the lengths above can be interpreted as approximate.

As described in this explanatory embodiment, the sensor (24) is placed before the pulleys (60, 61). The sensor can, however, be placed anywhere along the shaft, even after the pulleys, but mandatorily before the knives (51, 52), as what determines the cutting position is the relative distance between the sensor (24) , when the button is detected, and the intermediate part of the knives (51, 52), that is, L / 2. ------- In this realization, the PLC controls the process based on the digital information that arrives at the sensor set, to synchronize the pulleys or conductor and the knives. As described in the present invention, the movement and placement of the sugar cane stem is achieved by means of the pulleys or conductors driven by motors. Any suitable means of controlling the introduction of the rod into the cutting apparatus can also be used.

In addition, the cutting machine according to the present invention can use any suitable means of cutting the shank. In this realization, two circular knives are used, but other types of knives, harvesters, circular saws, plasma or laser cutting systems, etc. can also be used. In addition, the activation of the knives can be carried out by any appropriate means, using, for example, servomotors, pneumatic cylinders, hydraulic cylinders and the like. The machine elements for cutting the sugar cane can be determined by those skilled in the art.

In an alternative embodiment of the machine according to the present invention, several rods can be aligned simultaneously for cutting and the cutting can be carried out at once, in order to obtain several segments in a single cutting operation. This is the case, for example, when several sensors are aligned in parallel and each rod is inserted into each sensor and they are then positioned for cutting in parallel. In this embodiment, a guillotine-like cutting means can be used to cut several shank segments at once. Alternatively, more than one or all of the nodes on a single stem can be cut simultaneously, detecting the position of each node and cutting the stem segments using different cutting devices or activating certain knives, depending on the position of the knives. knots on the rod. --------- In another alternative embodiment, the sugar cane stem is not placed in the cutting position, but stands up and the cutting means are moved and placed in the cutting position of the segment with the desired feature.

In another embodiment, the unwanted characteristic of the stem may be the presence of injury or disease, such as caused by deteriorated pests or stem sections. Examples of pests that attack grassy plants, particularly sugar cane, are: Larvae such as Diatraea saccharalis and Telchin licus licus. Plant lice, such as Rhopalosiphum maidis and Melanaphis sacchari.

Beetles, such as Migdolus fryanus, Sphenophorus levis, Diloboderus spp, Euetheola spp, Ligynus spp, Stenocrates spp, Phytalus spp, Phyllophaga spp and several species of the Scarabaeidae family.

Termites, such as those of the family Termitidae, genus Cornitermes (for example, C. cumulates); and those of the family Rhinotermitidae (for example, Heterotermes tenuis, H. longiceps);

Nematodes, such as Meloidogyne spp, Helycotilenchus spp and Pratylenchus spp.

Grasshoppers such as Elasmopalpus lignosellus, Spodoptera frugiperda and Mocis latipes.

Cicadas, such as Notozulia entreriana, Deois schach, Aeneolamia selecta, Deois flavopicta, Mahanarva fimbriolata, Mahanarva posticata and Kanaina vittata.

These pests can cause a change in the stem structure. This change in the structure of the rod can be detected empirically by means of identification, such as the electromagnetic sensor or other types of sensors, as exemplified above. Alternatively? the rod may be deteriorated and this characteristic can also be detected empirically with the machine according to the present invention.

In this case, if the sensor identifies an unwanted characteristic, a digital signal can be sent to the PLC or CNC, ordering the disposal of a segment of the stem or the entire stem, if necessary. The disposal of the segment or the complete stem can be operated without cutting the segment and forwarding the stem until the unwanted characteristic is no longer observed on the stem and the desired characteristic is identified. The present invention also describes a method of cutting stem segments from a grass plant, which comprises identifying at least one stem characteristic using a sensor selected from the group consisting of a pressure transducer sensor, a capacitive sensor, an ultrasound sensor, an X-ray sensor, a magnetic sensor and a microwave sensor; placing the stem in a determined position for cutting, depending on the response of the mentioned sensor; and cutting the stem in a specific position, depending on the presence of the mentioned characteristic identified. Suitably, the method is conducted using the machine described above.

According to an adicoinal realization, when using an electromagnetic sensor in the method according to the present invention, water is applied to the rods before passing through the sensor, in order to increase the electrical conductivity of the rod and, thus, the identification of a desired or unwanted feature on the stem. Wetting of the stems can be achieved, for example, by spraying them with water or passing through a water bath before checking and cutting. The present invention also includes the prior verification of shank characteristics, for cutting at a later time. For example, a sensor can be used to detect a specific characteristic of the shank described above and the shank marked in the position of that characteristic to facilitate subsequent cutting. Stem marking can be performed using any appropriate means, such as a colored marker, UV mark or physical groove on the stem. A simple sensor system can be used later to detect the marker (in comparison with the complex sensor needed to detect the stem characteristic in the first place) for positioning the cut location. The present invention also includes a specific arrangement of an electromagnetic sensor, which is particularly useful for detecting characteristics on the stem of a grass plant, whose stems are rarely straight and can vary in diameter and length. It was observed that a better result can be achieved when the sensor surrounds the stem. In other words, the reading of certain characteristics on the stem is more accurate if the sensor is not only close to the stem, but also surrounds it due to differences from one stem to another.

A specific electromagnetic sensor arrangement in accordance with the present invention consists of an electromagnetic sensor comprising a frame with at least two electrodes of elongated thin metal plates arranged equidistantly around the perimeter of said frame.

In alternative embodiments of the present invention: the frame may have a circular, hexagonal, octagonal, quadrilateral or irregular shape; the / frame has a discontinuous perimeter; the panel comprises three to twelve electrodes; the panel comprises more than twelve electrodes; the electrodes are arranged at an angle to a cross axis of the frame; said angle is comprised between 0 ° and 90 °, particularly between 10 ° and 60 °, more particularly between 15 ° and 50 ° and, even more particularly, about —45 °; and / or the board is made of an electrical insulating material ^ --- Figures 4a to 4c represent a specific embodiment of the sensor (24) according to the present invention. The sensor (24) comprises a frame (241) that has two elongated electrodes (242). The picture shown in the drawings, according to this specific realization, has a circular shape. As technicians in the subject can deduce, however, the picture can take on different shapes, such as hexagonal or octagonal shape, or even a quadrilateral or irregular shape. The frame can guarantee any format determined by the technicians in the subject, as long as at least two electrodes are fixed equidistantly around the perimeter of the mentioned frame. The table can also comprise a continuous or discontinuous perimeter. By discontinuous perimeter, it can be interpreted that the table may have highlighted segments, such as segments of a circle. The frame may not even be located on its complete perimeter, as long as at least two electrodes are placed around the perimeter equidistantly. The panel must comprise at least two electrodes to generate an electric field and, consequently, a magnetic field. The figures illustrate an embodiment comprising eight electrodes (242), but more or less than eight electrodes can be arranged in the frame.

The electrodes (242) are manufactured with a metallic material to allow the passage of an electric current and the switchgear is preferably manufactured with an electrical insulating material, to avoid electrical interference with the electrodes. Such electrical insulating material can be, for example, a polymer, such as, but not limited to, polytetrafluoroethylene, nylon, polyester, etc.

As mentioned above, the electrodes must have a thin and elongated shape, so that they can flex flexibly and facilitate the passage of a rod through them. The dimensions of the electrodes, such as their length and thickness, can be determined by those skilled in the art, as long as the electrodes can flex without breaking when a rod is passing through them. The electrodes need to return to their original position after bending .__________________________ The electrodes (242) must be arranged equidistantly around the perimeter of the frame (241). “Equidistantly arranged” indicates that the electrodes must be equidistant from each other, taking into account the entire perimeter of the frame. In this specific embodiment shown in the figures, the electrodes are spaced 45 ° apart, as there are eight electrodes distributed over a 360 ° perimeter of the frame. As the technicians in the subject will deduce, a different number of electrodes will generate a different distribution, such as each electrode at 120 ° when three electrodes are present, 90 ° when four electrodes are present, 72 ° when five electrodes are present, and so on, taking into account a circular table. The same principle can be used for frames with different formats. In an octagonal shape, for example, eight electrodes can be arranged on each side of the octahedron.

In an alternative embodiment, the electrodes (242) are arranged in an angular position with respect to a cross axis of the frame. This angular position can be desired to facilitate the introduction of the rod into the electrode. The angle can vary within the range of 0 ° (that is, there is no angulation and the electrodes are parallel to the cross axis of the frame) to 90 ° (that is, the electrodes are perpendicular to the cross axis of the frame). Preferably, the angle is in the range of 10 ° to 60 °, more preferably 15 ° to 50 ° and, most preferably, about 45 °.

The electrodes can be connected by appropriate means to a metric (not shown) to allow the passage of an electric current to generate the electromagnetic field at these electrodes. Figure 9 is a schematic illustration of the sensor (24) according to the present invention that has a stem (40), particularly a sugar cane stem, which passes through it. ___________ It should be understood that, although the present invention has been described with respect to a specific embodiment, those skilled in the art can develop many technical and constructional variations without departing from the scope of the present invention. The attached claims, therefore, should be interpreted as covering all equivalents that fall within the scope and character of the present invention.

Claims

Claims (28)

1. CUTTING MACHINE (10), for cutting stem segments of a grass plant, comprising: - a sensor (24) to identify at least one characteristic of the stem (40); - means (60, 61) for placing the rod in a certain position for cutting, depending on the response of said sensor; and - stem cutting means; wherein said sensor to identify at least one characteristic of the stem, said means of placing the stem in a given position and said means of cutting the stem are interconnected and controlled by a control means (30) in order to cut the rod in a specific position, depending on the presence of the mentioned characteristic identified; characterized by the fact that the sensor is selected from the group consisting of a pressure transducer sensor, an ultrasound sensor, an X-ray sensor and a magnetic sensor. 2. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the stem is cut to a previously determined length (L). 3. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned stem (40) is a sugar cane stem (Saccharum spp), a bamboo stem (Bambusoideae) or a stem of elephant grass plant (Pennisetum purpureum). 4. CUTTING MACHINE (10), according to claim 1, characterized by the fact that said sensor to identify at least one characteristic of the stem is an X-ray sensor (24). 5. CUTTING MACHINE (10), according to claim 1, characterized by the fact that said sensor to identify at least one characteristic of the stem is a magnetic sensor (24). 6. CUTTING MACHINE (10), according to claim 5, characterized by the fact that said sensor is an electromagnetic sensor (24). 7. CUTTING MACHINE (10), according to claim 6, characterized by the fact that the aforementioned electromagnetic sensor (24) comprises two metallic surfaces between which the sugar cane rod passes. 8. CUTTING MACHINE (10), according to claim 7, characterized by the fact that water is applied to the rod before it passes between the metal surfaces. 9. CUTTING MACHINE (10), according to claim 7 or 8, characterized by the fact that the mentioned surfaces apply pressure to the stem when it passes between them. 10. CUTTING MACHINE (10), according to claim 8, characterized by the fact that the mentioned surfaces are cylinders. 11. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned means of cutting the rod are one or more among a knife, a circular knife, a reaper, a circular saw, a system of marking, a cutting system, a high pressure water cutting system, a plasma cutting system or a laser cutting system. 12. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned means of cutting the rod comprise two knives (51, 52) spaced from each other at a previously determined distance (L). 13. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned means (60, 61) of placing the rod in a determined position is one or more among rotating pulleys, conductive belt, conductive chain , tweezers or rollers, directed by appropriate means. 14. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned feature identified in the stem is the position of the node (42) in the stem. 15. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned feature identified in the stem is injury, presence of diseases or pests, or a deteriorated segment. 16. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the mentioned control means (30) is a Programmable Logic Circuit (PLC) or a Computer Numerical Control (CNC) system 17. CUTTING MACHINE (10), according to claim 1, characterized in that it additionally comprises a set connected to the mentioned means to identify at least one characteristic of the rod (24) to generate digital emission data (27) for the mentioned control means (30), wherein said set comprises a frequency generator (21), a configuration transformer (22), a frequency filter (23), a signal amplifier (25), a programmable digital processor (26) and a digital broadcasting device (27). 18. CUTTING MACHINE (10), according to claim 17, characterized by the fact that the mentioned frequency generator generates a voltage from 10 to 2000 Vpp. 19. CUTTING MACHINE (10), according to claim 17, characterized by the fact that the mentioned frequency generator generates a current of 50 to 500 mA. 20. CUTTING MACHINE (10), according to claim 17, characterized by the fact that the mentioned frequency generator generates a frequency from 800 kHz to 7.2 MHz ,. 21. CUTTING MACHINE (10), according to claim 1, characterized by the fact that several rods are cut substantially simultaneously. 22. CUTTING MACHINE (10), according to claim 1, characterized by the fact that several cuts of a single shank are carried out substantially simultaneously. 23. CUTTING MACHINE (10), according to claim 1, characterized in that the mentioned means of placing the shank in a determined position are replaced by means of placing the cutting means in the cutting position with respect to the shank . 24. CUTTING MACHINE (10), according to claim 1, characterized by the fact that the stem is not cut, but discarded when an undesired characteristic is identified in the stem. 25. CUTTING MACHINE (10), according to claim 2, characterized by the fact that the mentioned length (L) is in the range of 2 to 12 cm. 26. METHOD OF CUTTING STEM SEGMENTS FROM A GRASS PLANT, characterized by the fact that it comprises: a) identification of at least one stem characteristic using a sensor selected from the group consisting of a pressure transducer sensor, a sensor ultrasound, an X-ray sensor and a magnetic sensor; b) placement of the stem in a certain position for cutting, depending on the response of said sensor; and c) cutting the stem in a specific position, depending on the presence of the mentioned characteristic identified. 27. METHOD, according to claim 26, characterized by the fact that it additionally comprises the stage of wetting the stem before identifying the characteristic of the stem. 28. METHOD, according to claim 26 or 27, characterized by the fact that said feature is a knot (42) in the stem.