SPREADER WITH TORQUE MEASUREMENT CONTROL AT THE SPREADING EQUIPMENT AND IMPOSING THE CROSS-SECTION

Abstract

SPREADER WITH TORQUE MEASUREMENT REGULATION ON THE SPREADING MECHANISMS AND CROSS-SECTION CONTROL. The invention relates to a spreader (100) for organic matter (50) comprising a hopper (102), an opening (106), a motorized moving floor (104), motorized spreading mechanisms (110) mounted for rotation, a motorized door (112) movable at the opening (106), a weight measurement device for the hopper (102), a torque measurement device (118) for the spreading mechanisms (110), and a control unit (120) receiving the torque measurement, the weight measurement, the height measurement of the door (112), and the speed measurement of the moving floor (104), calculating the speed that the moving floor (104) must have to maintain a target mass flow rate based on this information, and controlling the first motorized system (108) to ensure that the moving floor (104) has this speed. Fig. 1

Description

Title of the invention: SPREADER WITH REGULATION BY MEASURING TORQUE AT THE SPREADING MEANS AND IM POSITION OF THE PASSING SECTION Technical field

[0001] The present invention relates to a spreader which makes it possible to spread organic matter on the ground and which is equipped with a system for controlling the moving floor based in particular on a measurement of the torque of the spreading members. STATE OF THE PRIOR ART

[0002] A spreader ensures the spreading of organic material such as manure on the ground.

[0003] The spreader conventionally comprises a box with an opening at the rear and a moving bottom, conventionally an endless belt, which is arranged in the bottom of the box and which receives the organic matter.

[0004] The spreader also comprises several spreading members arranged at the opening and which are mounted to move in rotation around vertical or horizontal axes to spread the organic matter at the rear of the spreader. Some versions comprise both members as described above to crumble the product to be spread and direct it towards discs with vertical axes whose main function is then dispersion on the ground by centrifugal projection.

[0005] Organic matter generally has variable densities because the mixture is not homogeneous.

[0006] To ensure balanced spreading of organic matter, different control systems are known but none are entirely satisfactory. Statement of the invention

[0007] An object of the present invention is to propose a spreader comprising a control system which is based on a measurement of the torque of the spreading members.

[0008] For this purpose, a spreader is proposed for spreading organic matter on soil, said spreader comprising:

[0009] - a box having an opening at the rear,

[0010] - a moving floor which is arranged in the bottom of the box and intended to receive the organic matter,

[0011] - a first motorized system arranged to drive the moving floor towards the opening,

[0012] - a speed measuring device arranged to measure the speed of the moving floor,

[0013] - several spreading members arranged at the opening and arranged for spread the organic matter at the rear of the spreader, where each spreading member is mounted to rotate,

[0014] - a second motorized system arranged to drive the spreading members in rotation,

[0015] - a door mounted so as to move vertically in translation on the body at the level of the opening,

[0016] - a third motorized system arranged to move the door alternately towards up or down to, respectively, widen or narrow the opening,

[0017] - a height measuring device arranged to measure the height of the door,

[0018] - a weight measuring device arranged to measure the weight of material organic material loaded into the box,

[0019] - a torque measuring device arranged to measure the torque consumed by the spreading organs, and

[0020] - a control unit arranged to receive the torque measurement from the device torque measurement, the weight measurement of the weight measuring device, the height measurement of the door of the height measuring device, the speed measurement of the moving floor of the speed measuring device, calculating a speed that the moving floor must have to meet a target mass flow rate from this information, and controlling the first motorized system so that the moving floor has this speed.

[0021] Advantageously, the second motorized system comprises a motor and a transmission system arranged between the motor and the spreading members and comprising a transmission shaft and the torque measuring device is arranged to measure the torque exerted on the transmission shaft.

[0022] Advantageously, the transmission system further comprises a distribution box and for each spreading member, a transmission subsystem, and the distribution box is arranged to transmit the rotation of the transmission shaft to each transmission subsystem.

[0023] Advantageously, the transmission shaft is connected to the second motorized system and to the distribution box through a universal joint.

[0024] Advantageously, the torque measuring device comprises two asymmetrical and metallic collars, each being fixed to one end of the transmission shaft, and, for each collar, an inductive sensor connected to the control unit and arranged to capture the position of said collar.

[0025] Advantageously, the torque measuring device is a torque meter mounted in series on the transmission shaft or on the universal joints. Brief description of the drawings

[0026] The above-mentioned and other features of the invention appear will become more clearly apparent from reading the following description of an exemplary embodiment, said description being made in relation to the attached drawings, among which:

[0027] [Fig-1] is a schematic representation of a spreader according to the invention,

[0028] [Fig.2] is a schematic representation of an example of a system of transmission implemented in a spreader according to the invention,

[0029] [Fig.3] is a side view of a collar implemented in the transmission system of [Fig.2],

[0030] [Fig.4] is a representation of signals measured by a measuring device torque implemented in the spreader according to the invention, and

[0031] [Fig.5] is an example of abacuses for models of evolution of the height of door according to the organic matter to be spread.

[0032] DETAILED DESCRIPTION OF EMBODIMENTS

[0033] [Fig.l] shows a spreader 100 according to the invention. The spreader 100 ensures the spreading of an organic material 50 on a soil.

[0034] The spreader 100 comprises a box 102 which has an opening 106 at the rear and the organic material 50 is stored in the box 102. The spreader 100 also comprises a control unit 120.

[0035] The spreader 100 also comprises a moving floor 104 which is arranged horizontally in the bottom of the box 102. The organic material 50 is deposited on the moving floor 104. The moving floor 104 takes for example the form of an endless belt mounted between several rollers 104a-b of which at least one (here the rear roller 104a) is driven in rotation by a first motorized system 108 controlled by the control unit 120.

[0036] Generally speaking, the first motorized system 108 is arranged to drive the moving floor 104 and the organic material 50 towards the opening 106 in a direction of movement from front to rear according to the arrow 10.

[0037] The spreader 100 also comprises a speed measuring device which communicates with the control unit 120 and which is arranged to measure the speed of the moving floor 104. The speed measuring device may be, for example, an inductive sensor, an optical sensor or the like.

[0038] The spreader 100 also comprises several spreading members 110 (here there are two) which can take different forms such as discs with blades or hedgehogs which extend over a greater height.

[0039] The spreading members 110 are arranged at the opening 106 and each spreading member 110 is mounted to be able to rotate about an axis which may be vertical or horizontal. Each spreading member 110 is thus arranged to spread or homogenize the organic matter 50 which it receives from the moving floor 104 at the rear of the spreader 100 when said spreading member 110 is driven by a movement of rotation.

[0040] The spreader 100 also comprises a second motorized system 114 controlled by the control unit 120 and arranged to drive the spreading members 110 in rotation.

[0041] In the embodiment of the invention shown in [Fig.l] and [Fig.2], the second motorized system 114 comprises a motor 114a and a transmission system 115 arranged between the motor 114a and the spreading members 110.

[0042] Here the transmission system 115 comprises a transmission shaft 116 which is arranged between the motor 114a and the spreading members 110 and the transmission system 115 ensures the transmission of the movement of the motor 114a to each spreading member 110. Thus any rotational movement of the motor 114a causes the rotational movement of the spreading members 110, in particular here through the transmission shaft 116.

[0043] The transmission shaft 116 is here arranged under the body 102 and it is mounted to be able to rotate relative to the body 102 by the installation at each of its ends of the bearings 208a-b.

[0044] The spreader 100 also comprises a torque measuring device 118 which communicates with the control unit 120 and which is arranged to measure the torque consumed by the spreading members 110 and which in the particular embodiment described here, corresponds to the torque exerted on the transmission shaft 116 and which is the resultant of the engine torque transmitted by the second motorized system 114 and the resistive torque of the spreading members 110 which are subjected to the organic matter 50.

[0045] The spreader 100 also comprises a door 112 which is mounted to move vertically in translation on the body 102 at the level of the opening 106. The door 112 is movable between an open position in which the door 112 does not block the opening 106 and a closed position, in which the door 112 blocks the opening 106.

[0046] To achieve this movement, the spreader 100 comprises a third motorized system which is controlled by the control unit 120 and which is arranged to move the door 112 alternately upwards or downwards to, respectively, widen or narrow the opening 106, as required.

[0047] In this embodiment, the door 112 is arranged between the spreading members 110 and the moving floor 102.

[0048] The spreader 100 also comprises a height measuring device which communicates with the control unit 120 and which is arranged to measure the height of the door 112. The height measuring device may be, for example, an inductive sensor, a cable sensor, an optical sensor, an ultrasonic sensor or the like.

[0049] The spreader 100 also comprises a weight measuring device which communicates with the control unit 120 and which is arranged to measure the weight of organic material 50 loaded in the box 102. The weight measuring device may be, for example, instrumented axis scales, strain gauges, extensometers, or others.

[0050] The control unit 120 is then arranged to receive the torque measurement from the torque measuring device 118, the weight measurement from the weight measuring device, the height measurement from the door 112 of the height measuring device, the speed measurement from the moving floor 104 of the speed measuring device, calculate an instantaneous mass flow rate passing through the spreading members 110 from this information, compare the instantaneous mass flow rate with a set mass flow rate and control the first motorized system 108 as a function of the result of the comparison and the height measurement.

[0051] Thus, the torque consumed by the spreading members 110 and which is exerted here on the transmission shaft 116 varies due to a change in density of the organic matter 50, the control unit 120 is immediately informed and it can modify the speed of the first motorized system 108 and therefore of the moving floor 104 in order to maintain a constant flow rate at the outlet of the spreading members 110.

[0052] The adaptation of the speed of the moving floor 104 is thus faster than in the case of the methods of the state of the art.

[0053] The torque consumed by the spreading members 110 has a short response time which allows precise regulation. Indeed, this torque physically represents the magnitude of mechanical energy necessary to tear the organic matter 50 from the pile present on the moving floor 104 and homogenize it and accelerate the mass of the organic matter 50 thus torn off to project it onto the ground.

[0054] These two energies add up and are of course proportional to the mass treated per unit of time, that is to say to the mass flow rate and the torque measurement at the spreading members 110 is therefore proportional to the mass flow rate and a complex calculation is not necessary to obtain it.

[0055] Furthermore, this torque measurement is insensitive to the vertical dynamic accelerations that the spreader 100 undergoes when it moves over uneven terrain.

[0056] Thus, when the instantaneous torque measurement decreases, this means that the density of the organic matter 50 decreases and it is then necessary for the speed of the moving floor 104 to increase to maintain the mass flow rate and the quantity of organic matter 50 spread. The control unit 120 then comprises means for controlling the first motorized system 108 so as to increase the speed of the moving floor 104.

[0057] Conversely, when the instantaneous torque measurement increases, this means that the density of the organic matter 50 increases and it is then necessary for the speed of the moving floor 104 to decrease to maintain the mass flow rate and the quantity of organic matter 50 spread. The control unit 120 then comprises means for controlling the first motorized system 108 so as to reduce the speed of the moving floor 104 when said torque measurement increases.

[0058] The first motorized system 108, the motor 114a and the third motorized system are preferably hydraulic motors powered from a power take-off of a tractor towing the spreader 100.

[0059] In the embodiment of the invention presented here, the transmission system 115 further comprises a distribution box 122 which is driven by the transmission shaft 116 and which transmits the rotation of the transmission shaft 116 to each transmission subsystem 202 via, for each spreading member 110, a transmission subsystem 202.

[0060] The distribution box 122 and each transmission subsystem 202 comprise mechanical components, such as sprockets, dogs, chains or the like, which make it possible to distribute the rotation around a horizontal axis of the transmission shaft 116 into a rotation around a vertical axis of each spreading member 110.

[0061] To ensure the transmission of rotations, even in the event of a lack of parallelism between the second motorized system 114 and the distribution box 122, the transmission shaft 116 is mechanically connected to the second motorized system 114 and to the distribution box 122 through a universal joint 124a-b.

[0062] According to a particular embodiment, the torque measuring device 118 comprises a torque meter mounted in series on the transmission shaft 116 or on the universal joints 124a-b upstream or downstream of these elements.

[0063] According to a particular embodiment of the invention shown in Figs. 2 and 3, the torque measuring device 118 comprises two collars 204a-b where each is asymmetrical and metallic. Each collar 204a-b is threaded and fixed to one end of the transmission shaft 116 (other embodiments are possible).

[0064] Each collar 204a-b has a first radius r on one half-turn, and on the other half-turn a second radius R greater than the first radius r. At each change of radius, the collar 204a-b has a step 302.

[0065] For each collar 204a-b, the torque measuring device 118 also comprises a sensor 206a-b such as an inductive sensor connected to the control unit 120 and arranged to capture the position of the associated collar 204a-b and in particular the passages at the level of the steps 302.

[0066] The two collars 204a-b are angularly offset around the transmission shaft 116.

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[0080] Such an arrangement makes it possible to measure the angular variation of the information coming from the two collars 204a-b or phase shift between the collars 204a-b, which corresponds to the torsion exerted on the transmission shaft 116 and therefore to the torque applied to it. According to a particular embodiment, the speed (vt in m / min) that the moving floor 104 must have to respect a target mass flow rate is given by the formula: ^=CT^x60 where Qm (kg / s) is the mass flow rate to be monitored, where Sx (m2) is the passing section of the door 112 when the moving floor 104 is at position x where x varies from 0 when loading to L0 when everything is unloaded and where L0 corresponds to the length of the moving floor 104 on which the organic material 50 is deposited, and where Mux (kg / m3) is the density at position x of the moving floor 104. The mass flow rate Qm is given by the formula: _ DxLwxv ~ 600x60 where D (kg / ha) is the desired dose entered by the user in a memory of the control unit 120, where Lw (m) is the working width and entered by the user in a memory of the control unit 120, and where v (km / h) is the tractor speed and entered by the user into a memory of the control unit 120. The through section Sx is a function of the value of the height of the door 112 given by the height measuring device and the width of the body 102 which is a fixed datum known to the control unit 120. The value of the height of the door 112 depends on the position x of the moving floor 104. In fact, depending on the position of the moving floor 104, the value of the height is determined by charts which associate a position x of the moving floor 104 with a value of the height of the door 112 and with a set speed vte of the moving floor 104. The height measuring device thus serves to confirm the position of the door 112 in order to correct it if necessary. [Fig. 5] shows models of the evolution of the door height for different organic materials 50, namely a cohesive type material (502), a medium type material (504) and a powdery type material (506). In [Fig. 5], the abscissa axis is representative of the distance traveled x by the moving floor 104 as a percentage of the length of the box 102 and the ordinate axis is representative of the height of the door 112 as a percentage of the height of organic material 50 loaded at the start which is entered by the user at the start and stored in a memory of the control unit 120.

[0081] The density Mux at position x of the moving floor 104 depends on the initial density (MuO) at loading and which is equal to the mass of organic matter 50 over its volume, where the mass can be evaluated from the data of the weight measuring device and the volume is evaluated from the volume of organic matter 50 in the box 102.

[0082] According to a particular embodiment:

[0083] - when the position x of the moving floor 104 is less than 7% of L0, Mux is equal at 0.6 * MuO,

[0084] - when the position x of the moving floor 104 is between 7% of L0 and 10% of L0, Mux is equal to MuO, and

[0085] - when the position x of the moving floor 104 is between 10% of L0 and 100% of L0, Mux is equal to (C / k) / (vt *Sx),

[0086] where C is the torque measured by the torque measuring device 118 and where k is the ratio between the mass of organic matter 50 lost and the integral of the torque since the start of the emptying.

[0087] Using these formulas and these different data, the control unit 120 can thus calculate the speed vt of the moving floor 104 to be applied, compare it to the set speed vtc and control the first motorized system 108 accordingly, that is to say in acceleration or in deceleration, so that the set speed vtc is equal to the speed vt, in other words, the control unit 120 calculates the speed vt that the moving floor 104 must have to respect the target mass flow rate from this information, and controls the first motorized system 108 so that the moving floor 104 has this speed vt.

[0088] This calculation of the speed vt is carried out continuously in order to regulate the moving floor 104 as best as possible.

[0089] [Fig.4] shows examples of signals transmitted by the inductive sensors 206a-b and processing carried out on these signals by the control unit 120 to calculate the torque.

[0090] For each graph, the x-axis is time and the y-axis is the signal value 0 or 1.

[0091] Graph 402 is representative of a first signal transmitted by the inductive sensor 206a near the second motorized system 114.

[0092] Graph 404 is representative of a second signal transmitted by the inductive sensor 206b near the distribution box 122.

[0093] Graph 406 is representative of a first calculated signal which is the result of the combination of the first signal 402 and a signal at 1 through a NAND gate.

[0094] The graph 408 is representative of a second calculated signal which is the result of the combination of the first calculated signal 406 and the signal of the other of the two 206b-a inductive sensors through a NAND gate.

[0095] Graph 410 is representative of a third calculated signal which is the result of the combination of the second calculated signal 408 and a signal at 1 through a NAND gate.

[0096] On the third signal 410, the time between two rising edges is equal to the rotation period of the transmission shaft 116 and the duration of a slot at 1 is proportional to the rotation period of the transmission shaft 116 and to the torsion angle of the transmission shaft 116 and therefore to the torque applied to it.

[0097] A method of controlling the first motorized system 108 corresponds to a process of managing the speed of movement of the moving floor 104 which consists first of all of a pre-spreading phase which typically lasts a few milliseconds. The pre-spreading phase corresponds to an initialization and is carried out before spreading, that is to say that the spreading members 110 are not subjected to any resistive torque from the organic matter 50. The pre-spreading phase is also carried out at the nominal rotation speed which generates a residual torque.

[0098] From the measurements of the inductive sensors 206a-b, the control unit 120 recovers the signals representative of these measurements, and applies the transformations described above to the different signals to obtain the third calculated signal 410 and from there, the duration of the slots for this residual torque and the rotation period of the transmission shaft 116.

[0099] The control unit 120 then calculates an offset as the ratio of the duration of the slots to the rotation period resulting from the third calculated signal 410.

[0100] A process for managing the speed of movement of the moving floor 104 then consists of a spreading phase which lasts the entire spreading.

[0101] The principle is similar to that of the pre-spreading phase. From the readings of the inductive sensors 206a-b and application of the transformations described above to the different signals, the control unit 120 determines from the third calculated signal 410, the duration of the slots for the instantaneous torque and the rotation period of the transmission shaft 116.

[0102] The control unit 120 then calculates a phase shift for this instantaneous torque as the ratio of the duration of the slots to the rotation period.

[0103] The control unit 120 then calculates the torsion undergone by the transmission shaft 116 as the difference between the offset calculated during the pre-spreading phase and the phase shift calculated instantaneously.

[0104] The torsion being proportional to the torque applied to the transmission shaft 116, the control unit 120 can then deduce the torque therefrom.

[0105] The spreading phase makes it possible to continuously update the speed of the first motorized system 108 as a function of the torque.

[0106] According to a particular embodiment, the control unit 120 comprises, connected by a communication bus: a processor or CPU (“Central Processing Unit” in English); a RAM (“Random Access Memory” in English); a read-only memory, for example of the ROM (“Read Only Memory” in English) or EEPROM (“Electrically-Erasable Programmable ROM” in English) type or of the Flash type; a storage unit, such as a storage medium of the HDD (“Hard Disk Drive” in English), or a storage medium reader, such as an SD (“Secure Digital” in English) card reader; and an I / O input / output interface manager.

[0107] The I / O input / output manager allows the control unit to interact with the various motorized systems and sensors.

[0108] The processor is capable of executing instructions loaded into the RAM from ROM, external memory, a storage medium (such as an SD card), or a communications network (not shown). When the human-machine interface is powered on, the processor is capable of reading instructions from the RAM and executing them. These instructions form a computer program causing the processor to implement the operating steps described above.

[0109] All or part of the steps and algorithms described here can thus be implemented in software form by executing a set of instructions by a programmable machine, for example a DSP (Digital Signal Processor) type processor or a microcontroller, or be implemented in hardware form by a machine or a dedicated electronic component (chip) or a set of dedicated electronic components (chipset), for example an FPGA (Field Programmable Gate Array) or ASIC (Application Specified Integrated Circuit) component. Generally speaking, the CTRL controller comprises electronic circuitry adapted and configured to implement the steps and algorithms described here.

Claims

Claims

1. A spreader (100) for spreading organic material (50) on soil, said spreader (100) comprising: - a box (102) having an opening (106) at the rear, - a moving floor (104) which is arranged in the bottom of the box (102) and intended to receive the organic material (50), - a first motorized system (108) arranged to drive the moving floor (104) towards the opening (106), - a speed measuring device arranged to measure the speed of the moving floor (104), - several spreading members (110) arranged at the opening (106) and arranged to spread the organic matter (50) at the rear of the spreader (100), where each spreading member (110) is mounted to be able to rotate, - a second motorized system (114) arranged to drive the spreading members (110) in rotation, - a door (112) mounted to move vertically in translation on the body (102) at the level of the opening (106), - a third motorized system arranged to move the door (112) alternately upwards or downwards to, respectively, widen or narrow the opening (106), - a height measuring device arranged to measure the height of the door (112), - a weight measuring device arranged to measure the weight of organic material (50) loaded into the box (102), - a torque measuring device (118) arranged to measure the torque consumed by the spreading members (110), and - a control unit (120) arranged to receive the torque measurement from the torque measuring device (118), the weight measurement from the weight measuring device, the height measurement of the door (112) from the height measuring device, the speed measurement of the moving floor (104) from the speed measuring device, calculate a speed (vt) that the moving floor (104) must have to respect a target mass flow rate from this information, and control the first motorized system (108) so that the moving floor (104) has this speed (vt).

2. Spreader (100) according to claim 1, characterized in that the second motorized system (114) comprises a motor (114a) and a transmission system (115) arranged between the engine (114a) and the spreading members (110) and comprising a transmission shaft (116) and in that the torque measuring device (118) is arranged to measure the torque exerted on the transmission shaft (116).

3. Spreader (100) according to claim 2, characterized in that the transmission system (115) further comprises a distribution box (122) and for each spreading member (110), a transmission subsystem (202), and in that the distribution box (122) is arranged to transmit the rotation of the transmission shaft (116) to each transmission subsystem (202).

4. Spreader (100) according to claim 3, characterized in that the transmission shaft (116) is connected to the second motorized system (114) and to the distribution box (122) through a universal joint (124a-b).

5. Spreader (100) according to one of claims 2 to 4, characterized in that the torque measuring device (118) comprises two asymmetrical and metallic collars (204a-b), each being fixed to one end of the transmission shaft (116), and, for each collar (204a-b), an inductive sensor (206a-b) connected to the control unit (120) and arranged to capture the position of said collar (204a-b).

6. Spreader (100) according to one of claims 2 to 4, characterized in that the torque measuring device (118) is a torque meter mounted in series on the transmission shaft (116).

7. Spreader (100) according to claim 4, characterized in that the torque measuring device (118) is a torque meter mounted in series on the universal joints (124a-b).

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