FR2683429A1 - VEHICLE SPREADING APPARATUS FOR CROPS, REMOTE CONTROL DEVICE OF SUCH AN APPARATUS AND METHOD FOR REMOTE CONTROL OF AN AGRICULTURAL APPARATUS. - Google Patents

Abstract

This spreading apparatus for crops, driven by a vehicle, is characterized in that it comprises several spray heads (11), supply means (3-4-5), serving to supply a liquid under pressure to the heads. sprayer (11), valve-function means for regulating the supply of liquid to the spray heads (11), actuation means, for opening and closing the valve-function means, control means , arranged to be operable from inside the vehicle and serving to regulate the supply of liquid to the spray heads (11), and a first emitting device (10) controlled by a device which is arranged to be operable outside the vehicle to remotely control the supply of liquid to the spray heads (11).

Description

-1 spreading device for crops, driven by a vehicle,

  The invention relates to the remote control of apparatus mounted on a vehicle, such as spreading apparatus for crops which are used for agricultural purposes. or horticultural, in which the spreading members are generally

  mounted on a tractor led by a single driver, also called below

  The expressor "mounted on a vehicle" includes devices mounted on

  trailers and self-contained devices.

  It is known to use spreading devices for crops which include spray heads carried on booms which extend transversely and are mounted behind a tractor or an airplane and which serve to disperse pesticides, herbicides, fertilizers or water on a field or on crops It is also known to provide specialized vehicles which are

  pushed by tractors or are self-propelled, such as spreaders

  dage for crops Generally speaking, such spreading devices

  for crops are designed to be controlled by a single operator.

  However, even specialized vehicles offer a restricted view of the spray heads through which the liquid is distributed, so that the operator must leave the vehicle to check that all the spray heads are working properly.

  It is generally possible for the operator to observe that the spray heads

  sations located at the far ends of the booms are working properly, but it is very difficult, and often impossible, for the operator to see from inside the cab if the spray heads near the vehicle are also working properly.

correct way.

  The distribution of the liquid by the spray heads is generally controlled by solenoid valves with spherical shutter or valves controlled by a motor, which are connected by cables to a control unit arranged in the cabin of the vehicle. Alternatively, the valves can be controlled by pneumatic or hydraulic power so that

  open or close the spray heads.

  In most cases, if the operator wishes to check the correct functioning of all the spray heads, he must interrupt the progression of the vehicle and go around it to its rear part, while the spray heads continue to function, in order to be able to carry out an examination

  visual of these spray heads.

  This procedure has many drawbacks. If the spray heads are in use, there is a loss of chemical substances and contamination of the soil and of the crops by overdosing. It has been found that with certain chemical substances, the soil overdosing may remain infertile for several years and crops grown on such land may contain excessive amounts of harmful chemicals which may be higher than permitted by food regulations. drives the vehicle out of

  chemicals can pollute rivers.

  There is also an operational safety problem which is posed by such a visual examination of the operation of the spray heads The operator may become contaminated himself Regulations concerning health and safety

  are intended to protect operators in hazardous environments

  gusts, but gusts of wind can project the sprayed product towards the operator in an easy and unexpected way In order to avoid the risk of contamination of the operator, the latter must generally walk in a circular arc of big

  dimension around the sprayer head ramps to avoid contamination

  nation This is time consuming and can result in crop damage

  in which the operator is walking.

  It was also found that a faulty operation of the spray heads

  This can be caused by the fact that the wiring provided between the control box and the spray head actuators is attacked by the

  corrosion or otherwise damaged and thus rendered faulty.

  This is why the present invention aims to provide a system that the operator can use in a safe manner by saving time and reducing

  costs in chemicals and that causes only minimal contamination

  ma Ie due to the spraying operation while the vehicle is stopped.

  The invention also remedies the need to provide control wiring between the location of the driver of the vehicle and the controlled actuator,

  for example a spray head valve.

  To this end, the subject of the invention is a spreading apparatus for crops, driven by a vehicle, characterized in that it comprises several spray heads, supply means, serving to supply a liquid under pressure to the heads. spraying means, valve function, for regulating the supply of liquid to the spray heads, actuation means, for opening and closing the valve function means, control means, arranged so as to be able to be operated from inside the vehicle and used to regulate the supply of liquid to the spray heads, and a first emission device controlled by a device which is arranged so that it can be actuated outside the vehicle in order to remotely control the supply of liquid to

spray heads.

  The remote transmitting and switching device can provide a coded signal for independently selecting and controlling the

  actuation means The coded signal can be an electromechanical transmission.

  genetic, e.g. radio transmission, optical transmission, infrared transmission or ultrasonic transmission Alternatively, a defined path may be provided in the form of an optical fiber, an electrical conductor

or even a mechanical connection.

  The first transmitting device can be operated using a number of positive start switches requiring pressure

  manual to maintain commissioning, so that the release of an inter-

  switch, for example a push button switch, disables an actuator. The coded signal intended to selectively control the actuators may include a security code used to confirm a signal transmission

valid.

  The first transmission device may include a direct transmission means

  tional A waterproof case preferably encloses the control device. A control device of this type can be mounted on an existing spreading device. This is why the invention also relates to a control device making it possible to remotely control a spreading device for crops, mounted on a vehicle, characterized in that it comprises a certain number of actuators, serving to control the apparatus, a first transmission device, comprising a certain number of switches and arranged so as to supply an encoded output signal according to the activation of the switches, and a certain number of remote receivers arranged so as to decode the coded signal and to operate the selected actuators, and in that the first coded output signal is intended to be transmitted in the air between the

  first transmitting device and each receiver.

  A second transmitting and switching device can be constituted by a control unit mounted in the driver's compartment of the vehicle and the first transmitting and switching device can be arranged so as to be portable so as to operate in tandem with the second transmission device,

  to allow the operator to control the device either from inside the vehicle

  cule, either from a location in the vicinity of the vehicle, but at a distance

of it.

  Preferably, the first transmitting and switching device is a hand-held transmitting device with which the operator can control

  selectively and independently different spray heads or different

  large groups of spray heads.

  Preferably, the switching device is arranged so that positive action is required of the operator to maintain the supply of liquid to the spray heads. This allows the liquid to be supplied by brief spurts to a spray head or to a group of spray heads only

  when a push button selection means provided on the communication device

  is kept in the "on" position.

  The switching device generally controls the spray heads.

  by communicating with a receiver mounted in or on the vehicle and

  arranged to supply the control signal for the action means -

  nement, for example to an electromagnet coil or a direct current motor associated with each liquid distribution valve However, each spray head may include an individual receiver which directly controls the actuation of this spray head Alternatively , a single receiver can be mounted in the control means provided in the vehicle and be arranged so as to act on these control means so that they control

  selectively the operation of the spray heads.

  If the communication channel between the first transmitting device and the receiver is in the visible or infrared spectrum, it may be necessary to provide lenses or parabolic reflectors making it possible to widen the range of the remote control device and to provide also screens, bells, reflectors, lenses or other means of directional alignment on the

  receiver, in order to eliminate a malfunction or reduction of sensitivity

  bility due to sunlight reaching this receiver As a variant, the signal coming from the transmitting device can also be coded so as to include a security code making it possible to confirm a valid signal If necessary, the receiver can be arranged so as to react only to two identical successive signals. The use of ultrasound as a means of transmission offers the additional advantage that they are practically unaffected by the spraying which

  could obscure the receiver and prevent the use of optical signaling.

  Although it is possible that the receiver is powered by an external source

  pending energy, it is preferably supplied from the vehicle's energy source, while the transmitting and switching device can be supplied independently with energy from a dry cell or '' a rechargeable battery It is generally preferable to enclose the transmitting device and the receiver in watertight and robust envelopes, in order to prevent

  spraying liquid to affect their operation.

  The receiver can include manual switches which can be locked in the "on" or "off" position in order to control the actuating means. The operator generally controls the supply of liquid to the spray heads or groups of spray heads. using these

  switches locked, from the driving position inside the vehicle.

  When the operator wishes to ensure that the spray heads are working properly, he immobilizes the vehicle, switches the locked switches to the "stop" position and leaves the vehicle with the emission and switching device.

  at a distance It then goes directly to the rear of the vehicle at a sufficient distance

  health to avoid contamination when the spray heads are in service The operator then activates the switching device by pressing one or more of the desired buttons in turn in order to cause brief spray sprays supplied by the spray heads selected By a visual examination, the operator then identifies any blocked nozzles and he can take the necessary action to remedy the blockage He can then carry out a new test remotely from the spray heads Once these

  all are in working order, the operator can return directly

  the vehicle and continue spreading using the switches located on the receiver unit so as to control the supply of liquid to the spray heads. It is planned to bring into force in the United Kingdom and in Europe anti-pollution laws requiring that the spray nozzles operate within defined limits of tolerance vis-à-vis their particular initial parameters of

  operation The present invention is particularly usable in operations

  test and calibration rations of the different nozzles to ensure permanent compliance with legal provisions To calibrate a nozzle, the operator holds a graduated bottle above each nozzle successively and operates the desired nozzle for a pre-set period so that the flow can be

  controlled and that a corrective action is carried out for each nozzle in turn.

  This is why the invention also relates to a method for remote control of an agricultural device, characterized in that it consists in transmitting an ultrasonic or electromagnetic signal from a first transmitting device to a receiver which is arranged so as to control an actuator selected at the

  reception of a selectively coded signal, so as to control the apparatus.

  The invention will be described by way of example with reference to the diagrammatic drawings.

  attached ticks of which: FIG. 1 represents a side view of a tractor vehicle on which a spreading apparatus for crops is mounted, FIG. 2 represents a rear view of the whole of the tractor and of the spreading apparatus for crops of FIG. 1, FIG. 3 represents a specialized vehicle with spreading apparatus for crops and an operator controlling this apparatus remotely, FIG. 4 represents a front perspective view of a receiver, FIG. 5 represents a view in rear perspective of this receiver, FIG. 6 represents a perspective view of a transmission device intended to be used with the receiver,

  FIG. 7 represents the circuit diagram of an emission unit in infra-

red,

  FIG. 8 represents the circuit diagram of an infra-red reception unit

  red, FIG. 9 represents a circuit diagram making it possible to adapt existing spreading apparatuses for crops so that they function in a manner in accordance with the invention, FIG. 10 represents the circuit diagram of a unit reception device adapted so as to be used with a specialized apparatus for spreading crops using the invention, FIG. 11 represents a circuit diagram of a radio transmission unit, FIG. 12 represents a radio reception unit intended to be used with the radio transmitting device of Figure 11 and Figure 13 shows a current source switching arrangement which is provided for an actuator driven by a motor and used with the

  radio transmission system shown in Figures 11 and 12.

  Referring to the drawings, FIG. 1 represents a tractor 1 comprising a cabin 2 and a crop spreading device which is mounted at the rear of the tractor This crop spreading device essentially consists of: of a

  liquid tank 3 and two spreading booms 4 and 5 extending transversely

  Lement These booms 4 and 5 carry spray heads which are connected to the tank 3 via a number of control valves which

  control the supply of these spray heads with pressurized liquid.

  The valves used to control the supply of the spraying heads with liquid are operated from inside the cabin 2 using a control box 6 This control box 6 is arranged so as to emit signals used to controlling actuator control valves which are associated with the spray heads The control unit 6 may comprise a receiver or it may be coupled to a receiver mounted inside the window

  rear or on the cab roof, respectively in positions 7 and 8 shown

shown in Figure 1.

  If we also refer to figure 2, the receiver can be mounted on

  the spreading apparatus for crops in a position 9 close to the ramps 4 and 5.

  If the receiver is mounted outside the cabin or in a position in which it can be affected by the spray distributed by the crop spreading device, it must be waterproof and robust A transmitter or device or hand-held transmitting unit 10 (as shown in Figure 6) is arranged to communicate with the receiver from a remote position located at the rear of the vehicle, using transmission by ultrasound or with electromagnetic radiation such as infrared or radio transmission Transmission by ultrasound is more particularly usable if the spreading conditions obscure an infrared transmission Alternatively, under such poor transmission conditions , the transmitter can communicate with the receiver via a cable which can be a fiber optic cable, an electric cable or even a mechanical connection In most art of the conditions of spreading, the preferable transmission is the infrared transmission since this allows the greatest flexibility of use on the part of the operator and avoids a possible malfunction if the signal is located in a part

  crowded with the radio frequency spectrum.

  The booms 4 and 5 carry a number of spray heads 11 which are adjustable in groups of five. Two groups of spray heads are arranged on the boom 4 and two other groups of spray heads are mounted on the boom 5, the fifth group of spray heads being mounted

  directly behind the vehicle, in section 12.

  FIG. 3 represents a specialized vehicle with a spreading apparatus for crops, comprising articulated ramps 4 and 5, and an operator 13 standing at a remote location at the rear of the vehicle The operator 13 holds the transmitter 10 hand which has a certain number of buttons, each of which can be used to produce a coded signal intended for a receiver 14 mounted at the upper part of the rear window of cabin 2 of the vehicle. The coding can be coded by frequencies or digital coding on a

single frequency.

  If reference is also made to FIGS. 4, 5 and 6, the receiving unit shown in FIGS. 4 and 5 is housed in a waterproof enclosure 15 which comprises five switches 16, mounted on the front wall which faces in the cabin, and an infrared receiver element 17 mounted on the rear wall which can be applied

  against the rear window of the cabin using suction cups or mounting arms 18.

  This receiving unit is supplied with current using a cable and plug

to jack 19.

  The infrared receiver element 17 receives signals from an infrared transmitter element mounted in the end wall of the transmission unit shown in FIG. 6 The upper face of this transmission unit 10 comprises six irnt 9 switches push button 20 grouped in three rows

  containing respectively three switches, two interrupters and a switch.

  The intept Jpteuis s; ort numbered so as to identify the sec ion of spray heads.

  risatio N they control The switch 6 coarn 1 iarcie sirnrulianénent all spray heads It will be understood that ii can be provided additional buttons and that other groups of spray heads can be controlled simultaneously However, the switches are grouped according to the formation considered in the preferred embodiment of the invention, given that the spreading apparatuses for crops generally comprise either three,

  or five groups of spray heads.

  The circuit arrangement provided for the transmitting unit 10 is represented in FIG. 7. If one also refers to this FIG. 7, the circuit is supplied by a dry cell battery 21 coupled to the transmitter circuit by the via an ON / OFF switch 22 An integrated circuit remote control transmitter 23 is connected to the six switches 20 This integrated circuit transmitter 23

  is sold under the reference SL 490 and provides a basic multichannel system used

  reading a pulse position code to provide up to sixteen different channels of communication The coding and modulation method provides good noise protection and a range of up to ten meters and, if a greater range or higher selectivity is necessary, parabolic reflectors can be filtered for the emitter and / or

  receiver The transmitter 23 is activated when one of the inter-

  switches 20 and it supplies a coded signal which is modulated on the infrared output frequency obtained from emitter diodes 24 These emitter diodes 24 are controlled by a transmitter-follower circuit 25 which modulates the coded output signal from the transmitter 23 on the infrared frequency emitted by the diodes 24 The rate of the transmission unit, in pulses per minute (I / min), should be chosen

  so as to avoid harmonic or fundamental frequencies of the surrounding environment

  The operating frequency, for example the frequency of transmission of the national network which comes from local pylons In order to avoid unintentional actuation or actuation from external sources other than the transmitter 10, the receiver is designed so as not to react only to two successive signals which it recognizes as valid signals for the functioning of the system. Referring to FIG. 8, the reception unit comprises the infrared receiver element 17 coupled to an infrared preamplifier with integrated circuit 26 (sold under the reference SL 486) The coded signal coming from the transmitter 10 which is received by element 17 is amplified by this high gain integrated circuit 26 and is applied directly to an integrated demodulation and decoding circuit 27 (sold under the reference ML 926) The output provided by the integrated circuit 27 is in the form of a number of four-bit binary signals which

  are decoded using an ET 28 door group so as to supply one, selected

  tiated, output conductors 29 which each control an actuator relay 30 The contacts of these five relays 30 are represented by the contacts 31 which supply the current to the actuation means serving to open

  and adjust the valves allowing the liquid to reach the spray heads.

  It will be understood that any of the relays or more of them

  can be operated to open and close a selected spray head

  or a group of selected spray heads It will also be understood that the embodiment described can be adapted to other vehicles such as an airplane The type of vehicle can move on land, on water or in air and the type of device ordered may, if necessary, be of a type other than

spreading device.

  FIG. 9 schematically represents the switching arrangement provided for spreading apparatuses for crops which are constructed so as to implement the present invention The relays 30 represented in FIG. 8

  can also be actuated by the switches 16 shown in FIG. 4.

  As FIG. 9 shows, the switches 16 are represented by inter-

  breakers Si to 55 These switches Si to 55 energize the solenoid coils which control the supply of the spray heads

  liquid These switches Si to 55 are connected to the existing wiring by means of

  diary of a multiconductor cable 32 leading to the electromagnet coils which actuate the valves controlling the supply of the spraying heads with liquid The contacts 31 of the relays 30 are represented in FIG. 9 by the relay contacts RL 1 A to RL 5 A The closing of one or more of these relay contacts RL 1 A to RL 5 A couples the source 33 constituted by the vehicle battery to the

  selected electromagnet coil corresponding to the section of spray heads

rization selected.

  If we refer to Figure 10, the wiring diagram is similar to that of

  Figure 9 and the comparable elements are designated by the same references.

  However, in the embodiment shown in FIG. 10, the switches and relays can be contained inside the envelope provided for the control unit.

  reception, so that by manually selecting one or more of the inter-

  breakers If at 55 inside the cabin or by actuating one or more of the relays using the transmitter 10 remotely, current is supplied by the vehicle battery 33 to the electromagnet coils 34 which actuate the valves of

  control to supply the spray heads with liquid.

  In operation, and with particular reference to FIG. 3, an operator can check the effective operation of the spray heads of the crop spreading device, by carrying out the following operations First, he cuts the device spreading when the vehicle is stationary, by operating the switches provided on the receiver control unit Secondly, the operator then descends from the cab of the vehicle and goes directly to the rear of the vehicle as shown in Figure 3, if necessary by passing above or below the ramp Third, in

  using the buttons provided on the transmitter 10 and actuating each of the button switches numbered 1 to 5 sequentially one after the other

  the other, it can carry out a visual examination of each spray head in order to check whether the spray heads are clogged or not or work or not in a satisfactory manner The spray heads only work while the corresponding switch button is pressed It will be understood that this allows the operator to actuate the spray heads for a minimum time sufficient to control their operation, but without causing an excessive release of dangerous chemical substances which could otherwise contaminate the soil

  at the location considered After checking the operation of the spray heads,

  sation, the operator eliminates a possible blockage if necessary Finally, the ope

  rator can return directly to the cab of the vehicle and continue to spread on crops, using the switches associated with the crop box.

  control located in the cabin to select the sprayer head sections

station in service.

  The invention also allows an operator to control the correct calibration.

  spray heads This is usually done before the sprayer

  dage is not brought to the field In this calibration operation, each spray head which is to be tested is connected to a reservoir, which can be provided with a graduation, so that it collects all the liquid supplied by the spray head during a pre-set period If the tank is provided with a scale, it provides an immediate measurement of the flow rate, while, if it is not provided with a scale, the collected liquid can then be poured in one

  graduated bottle Calibration can be carried out on the nozzles one by one or simultaneously

  n on nozzle groups The nozzles can be opened and closed from the control unit located in the vehicle or from a device

remote control.

  It will be understood that, although the main use of the invention consists in controlling dangerous chemical substances, for example pesticides, herbicides, fertilizers and similar liquids used in agriculture and horticulture, the invention can be adapted to d other uses applied to other fluid distribution systems It will also be understood that, although the vehicle is in general a tractor or a spreading vehicle for crops which is moved by means of wheels or tracks, the invention can be adapted for use with

  spreading planes or helicopters for crops.

  As indicated above, the remote signaling is preferably of the ultrasonic or electromagnetic type, for example by the

  light, infrared radiation or any other suitable means of transmitting

  signal coding can be used provided that it allows operation

  erator to selectively operate a device located at a distance, consisting for example of spray heads, from a location in the vicinity of

  this For testing purposes, the location should be on the observation line.

  visual indication, although for general operation the signaling may

  be made from inside the driver's compartment of the vehicle.

  The embodiment shown in FIGS. 11 to 13 represents a radio transmission system used to control an actuator driven by a motor, for example a ball valve shutter driven by a motor which opens and closes the spray heads. FIG. 11 represents the radio transmitter equivalent in operation to the transmitter of Figure 7 This radio transmitter consists of a UHF signal transmission card 35 whose output is transmitted by an antenna 36 The coded output provided by this antenna 36 is determined

  by the push-button selection switches 37 and by the logic circuit 38.

  The radio receiver shown in FIG. 12 comprises a UHF radio reception card 39 receiving the signals supplied by the antenna 40 The output of the reception card 39 is sent, via a logic circuit 41, to

  relays 42 with which contact groups 43 are associated.

  FIG. 13 shows in more detail the arrangement of a group of relays 44 which is controlled by the radio receiver and a reversing switch 45 which is mounted in the cabin of the vehicle. A source of direct current at twelve volts is connected to the terminals 46 The output of the reversing switch 45 is connected to the terminals 47 and 48 respectively of the contact group 44 Depending on the position of the switch, the output terminals 49 and 50 receive a positive or negative 12 volt voltage When the group relay 44 is in a position

  given, the polarity at terminals 49 and 50 can be reversed by actuating the switch

reversing contactor 45.

  Terminals 49 and 50 are connected to a valve driven by a motor

  direct current which controls the supply of spray heads with liquid.

  Although, in the embodiments described, the actuators are powered

  in energy from an electric source, it is possible to power the action-

  energy from a pneumatic or hydraulic line available on the vehicle or from the supply pressure of the liquid spreading device In such cases, the wiring can be omitted and the receiver and the 'transmitter

  radio can be powered by solar energy using a rechargeable battery

  geable. It will be understood that the invention can be adapted so as to control other types of agricultural machines and the like, for example a conveyor grading line for potatoes for which the operator may wish to wear a remote control device allowing him of

  control this line when it is away from the main control unit.

  The invention makes it possible to practically eliminate the pollution of the environment which would result from excessive doses of toxic chemical substances, firstly because the nozzles of the spray heads can be subjected to a clogging test using only one minimum spray pattern, while controlling each spray head individually Second,

  because the calibration operation is facilitated, the operator of the spreading apparatus

  dage can regularly calibrate each nozzle to ensure that

  the spray heads operate within the legal limits.

  The invention ensures operator safety, since it allows the operator to stand well outside the scope of spraying and to remain at

  control distance of the spreading device so as to interrupt the feeding

  if the wind were to start gusting in its direction.

  The operator can instantly cut power by lifting a finger from the button.

  It can then move to a safer position from which it can still provide signaling between the transmitter and the receiver and be on the line.

  spray head observation.

  By adapting the invention so that it can be used on existing crop spreaders or by using the invention on a specially designed crop spreader or other vehicle-mounted device, the advantages are a gain considerable time in the test operation and a financial saving concerning the chemicals lost by the spreading apparatus, while, for the control of a general apparatus, there is also an improvement with regard to rupture or the failure of the

control wiring.

  Since the operator constantly controls the spreading control

  Even if it happens to be outside the booth, the invention provides an improved safety factor. The limitation of the time during which a spray head is controlled under test conditions also results in a

  reduced risk of operator and soil contamination.

Claims (20)

  1 spreading apparatus for crops, driven by a vehicle (1), characterized in that it comprises several spray heads (11), supply means (3-4-5), serving to supply a liquid under pressure at the spray heads (11), valve function means for controlling the supply of liquid to the spray heads (11), actuation means for opening and closing the valve function means, control means, arranged so that they can be operated from inside the vehicle and serving to regulate the supply of liquid to the spray heads (11), and a first emission device (10) controlled by a device which is arranged so that it can be actuated outside the vehicle (1) for remote control of the supply of liquid to the spray heads (11).   2 spreading apparatus for crops according to claim 1, characterized in that the remote transmission and switching device (10) provides a coded signal used to independently select and control the actuation means.   3 spreading apparatus for crops according to claim 2, characterized   in that the coded signal is an electromagnetic transmission.   4 spreading apparatus for crops according to claim 2, characterized   in that the electromagnetic transmission is a radio transmission.   5 spreading apparatus for crops according to claim 2, characterized   in that the electromagnetic transmission is an optical transmission.   6 spreading apparatus for crops according to claim 2, characterized   in that the electromagnetic transmission is an infrared transmission.   7 spreading apparatus for crops according to claim 2, characterized   in that the coded signal consists of an ultrasonic transmission.   8 spreading apparatus for crops according to any one of   Claims 1 to 7, characterized in that the first transmitting device (10) is   operated by a number of positive start switches (20) requiring manual pressure to maintain start up, so that   releasing a switch (20) disables an actuator.   9 spreading apparatus for crops according to claim 9, characterized   in that the switches (20) are push button switches.   Apparatus for spreading crops according to any of the claims   dications 1 to 9, characterized in that the coded signal intended to selectively control the actuators includes a security code used to   confirm a valid signal transmission.   11 Spreading apparatus for crops according to any one of the claims   dications 1 to 10, characterized in that the first transmitting device (10)   includes a directional emission means.   12 spreading apparatus for crops according to any one of the claims   dications 1 to 11, characterized in that a waterproof housing (15) encloses the control device.   13 Control device making it possible to remotely control a spreading device for crops, mounted on a vehicle, characterized in that it comprises a number of actuators, serving to control the device, a first device for transmission (10), comprising a number of switches (16, 20) and arranged so as to provide a coded output signal according to the activation of the switches, and a number of remote receivers (17) arranged so as to decode the coded signal and operate the selected actuators, and in that the first coded output signal is intended to be   transmitted in air between the first transmitting device (10) and each receiver.   14 Control device according to claim 13, characterized in that   that with each actuator, there is associated a receiver.   Control device according to any one of claims 13   and 14, characterized in that a second emission device mounted on the vehicle   is designed to control the actuators using the remote receiver.   16 control device according to claim 15, characterized in that the second coded output signal is provided so as to be transmitted in the air,   between the second transmission device and each receiver.   17 Control device according to claim 13, characterized in that the remote transmission and switching device (10) provides a coded signal used to independently select and control the means actuation.   18 Control device according to any one of claims 13   to 17, characterized in that the first transmitting device (10) is controlled by a number of switches (20) having a transmitting device (10) in positive service which requires manual pressure to maintain this setting service, so that releasing a switch (20) disables an actuator. 19 Control device according to claim 18, characterized in that   that the switches (20) are push button switches.   Control device according to any one of claims 13   3 S to 19, characterized in that the coded signal intended to selectively control the actuators comprises a security code making it possible to confirm the transmission of a valid signal.   21 Control device according to any one of claims 13   to 20, characterized in that the first transmitter (10) comprises means for transmitting directional sion (36).   22 Control device according to any one of claims 13   to 21, characterized in that a waterproof envelope (15) encloses this device control.   23 A method of remote control of an agricultural device, characterized in that it consists in transmitting an ultrasonic or electromagnetic signal from a first transmitting device (10) to a receiver which is arranged so as to control a selected actuator , upon receipt of a coded signal so   selective, so as to control the device.