Actuator assembly, valve assembly, and plant treatment agent application device and method

Abstract

The invention relates to an actuator assembly (38) for actuating a valve (32), in particular a valve (32) of a plant treatment agent application device (20), by means of a main electric motor (34). The main electric motor (34) is coupled to a valve actuator (60) of the valve (32) by means of a rotation-translation converter (36) in order to open the valve (32) at least once and close the valve at least once, for each revolution of a rotary member of the rotation-translation converter (36), in order to establish a valve opening angle range per revolution, wherein the rotation-translation converter (36) can be adjusted by means of an adjustment device (78), in order to change the valve opening angle range per revolution and / or an opening speed and / or a closing speed.

Description

Betätiqunqsanordnunq, Ventilanordunq und Pflanzenbebehandlungsmittel-Austragnqunqs- vorrichtung und -verfahren

[0001] The present disclosure relates to an actuating arrangement for actuating a valve of a plant treatment product application device.

[0002] Furthermore, the present invention relates to a valve arrangement with a flap valve and such an actuating arrangement, as well as a plant treatment agent application device with such a valve arrangement and a corresponding method.

[0003] In the field of pesticide application devices, it is known to arrange a plurality of valve assemblies on the valve bar of a field sprayer, each of which is assigned a nozzle for applying pesticides. Such field sprayers can be mounted on tractors or other field implements so that the valve bar is oriented transversely to the direction of travel. This allows large planted areas to be treated efficiently with pesticides. The nozzles on the valve bar can be adjustable to accommodate different row spacings.

[0004] From the document Wegener, Jens Karl: More targeted and flexible - Trends in crop protection technology. In: Frerichs Ludger (ed.): Yearbook of Agricultural Technology 2019. Braunschweig: Institute for Mobile Machines and Commercial Vehicles, 2020. pp. 1-7, it is known that pulse width modulation (PWM) enables different application rates at approximately the same pressure and droplet size using only one nozzle size. This is achieved by switching the nozzles on and off at high frequencies, with the pulse width determining the flow rate. According to this document, current systems operate at 10 to 50 Hz.

[0005] Document US 2015 / 0375247 A1 discloses a spray system with dynamic presets for controlling spray nozzles, each of which can be individually controlled continuously or according to a time-modulated or frequency-modulated electronic Signal control systems operate to dispense liquid droplets. Adjacent or closely adjacent nozzles are collectively controlled in terms of their timing by various operating modes or physical configurations at each spray nozzle. The spray nozzles can be mounted on a variety of attachments, including agricultural or industrial spray booms.

[0006] Document US 2022 / 0410195 A1 discloses a valve control system for agricultural products. A method used in this system to prevent voltage spikes employs a multitude of valves divided into subgroups. Supply to the subgroups occurs with a time delay based on the vehicle speed and the total number of valves in the multitude. Furthermore, valves can be actuated sequentially with their respective subgroups subjected to time delays. This document proposes a solenoid valve controlled by pulse-width modulation.

[0007] With such solenoid valve arrangements, the current draw is relatively high because the magnetic system used has a relatively low efficiency. In some cases, the current draw of such a valve arrangement can reach 1 A in the actuated state. Since field sprayers can have a width of up to 36 m, a current of 90 A must therefore be supplied for, for example, 90 nozzles in the prior art. The method described in document US 2022 / 0410195 A1 can reduce the instantaneous current load. However, this may prevent sufficiently flexible or uniform adjustments to vehicle speeds and / or application rates per unit of time.

[0008] In magnetic systems, the magnetic force is determined by the current. Depending on the distance to the source, voltage drops occur in the line supplying power to the spray arm, thus changing the force in the solenoid valve and consequently its dynamics.

[0009] It is therefore an object of the invention to provide an improved actuating arrangement, an improved valve arrangement, an improved plant treatment agent- to specify a discharge device and a corresponding method that have a better efficiency with regard to the actuation of the valves.

[0010] This problem is solved by an actuating arrangement for actuating a valve, in particular a valve of a plant treatment application device, by means of a main electric motor, wherein the main electric motor is coupled to a valve actuator of the valve by means of a rotary-translation converter in order to open and close the valve at least once with each revolution of a rotary element of the rotary-translation converter in order to establish a valve opening angle range per revolution, wherein the rotary-translation converter is adjustable by means of an adjusting device in order to change the valve opening angle range per revolution and / or an opening speed and / or a closing speed.

[0011] In the actuation arrangement according to the invention, a valve opening angle range per revolution is thus variably set, which corresponds to setting a variable duty cycle in a PWM control. The actuation frequency of the valve is set by the speed of the main electric motor. If, for example, the speed is increased, the actuation frequency of the valve is also increased. However, the valve opening angle range per revolution of the rotary element of the rotary-translation converter remains unchanged.

[0012] The main electric motor can be directly connected to the rotary element of the rotary-translation converter, but can also be connected to it via a gear arrangement, so that the speed of the rotary element of the rotary-translation converter is proportional to the speed of the main electric motor.

[0013] The adjusting device therefore allows the flow rate or output quantity to be controlled, preferably regulated, for a given speed of the main electric motor by controlling or regulating the valve opening angle range per revolution.

[0014] The adjustment by means of the adjustment device is preferably motorized, in particular electromechanical.

[0015] In some embodiments, the adjusting device can change the valve opening angle range per revolution of the rotary element of the rotary-translation converter, i.e., the angular range per revolution within which the valve is open. Alternatively or additionally, in some cases, the adjusting device can also change an opening speed and / or a closing speed. This means that the rotational angular range of the rotary element intended for the transition from a closed position of the valve to an open position can be changed in order to alter the valve opening speed at a predetermined rotational speed of the main electric motor. Similarly, the adjusting device can, if necessary,a rotation angle range is changed within which the valve position is adjusted from the open position to the closed position, consequently changing the closing speed (at a given speed of the main electric motor).

[0016] The valve is actuated by controlling a main electric motor, which is coupled to a valve actuator via an adjustable rotary-translation converter. This type of valve actuation allows for a high degree of freedom regarding the valve's opening and closing times, particularly with respect to the metering of fluids through the valve.

[0017] The electric motor can be designed as a BLDC motor. With this type of motor, the speed is determined by the electronics and software. This makes it possible to maintain a constant speed even during voltage drops.

[0018] The rotary-translation converter can be implemented in various ways, for example via a camshaft, a coupling gear or similar.

[0019] The above problem is further solved by a valve arrangement with a flap valve and an actuating arrangement of the type according to the invention.

[0020] In this context, a flap valve is understood to be a valve comprising a flap or lever that is pivotable about an axis and on which a sealing element is formed for sealing a valve seat of the valve. An example of such a flap valve is described in document EP 1 811 216 B1, to whose entire disclosure with regard to the actuating arrangement and the flap valve itself reference is made in full.

[0021] Finally, the above problem is solved by a plant treatment product application device with at least one valve arrangement of the type according to the invention and by a method for applying plant treatment products by means of such a plant treatment product application device, comprising the step of controlling an application quantity during a drive over a planting area as a function of a driving speed and / or another parameter by actuating the valve.

[0022] Since an electric motor generally has a significantly higher efficiency than an electromagnet, the actuation of a valve, such as a directional control valve, can be achieved with much lower currents than with the control of a proportional valve. Preferably, the maximum current consumption of a valve arrangement of the type according to the invention is less than 0.5 A, since the electric motor is preferably a DC motor with an efficiency between 90 and 95%.

[0023] On the other hand, the maximum actuation frequency of the valve should be less than 50 Hz, especially less than 40 Hz. A typical value is 30 Hz.

[0024] The preferably used directional control valve (especially a butterfly valve) preferably has only two valve positions: an open position and a closed position. In contrast to so-called proportional valves, the control can therefore be implemented very simply, using pulse width modulation. Such directional control and butterfly valves are also significantly more robust than proportional valves, where the flow rate is regulated by precisely adjusting a flow gap.

[0025] The task is thus completely solved.

[0026] Preferably, the rotary-translation converter has a camshaft driven by the main electric motor with a cam assembly arranged thereon which acts on the adjusting element, wherein the cam assembly has at least two different cam contours which define different valve opening angle ranges per revolution of the rotary element of the rotary-translation converter and / or different opening speeds and / or different closing speeds, wherein the adjusting device is configured to set up one of the cam contours to act on the adjusting element at any given time.

[0027] Each of the cam contours preferably extends through 360°, so that, with continuous drive by the main electric motor, the respective cam contour is traversed once per revolution of the rotary element of the rotary-translation converter. In this embodiment, the rotary element is the driven camshaft. The camshaft can be driven directly by the main electric motor or via a gear arrangement, thus establishing a gear ratio.

[0028] Once a cam profile is set, this results in a ratio of opening angle range to closing angle range per revolution, defined by that cam profile. This ratio corresponds to a duty cycle and cannot be changed for that cam profile. To change the duty cycle, or the ratio of opening angle range to closing angle range, the adjustment mechanism is activated to switch to a different cam profile.

[0029] It is preferred if the different cam contours are arranged adjacent to each other along a longitudinal axis of the camshaft.

[0030] This allows the cam contours to be brought into engagement with the valve actuator by axial adjustment in relation to a predetermined position.

[0031] To ensure the smoothest possible transition between the cam contours, it is preferred if the different cam contours blend seamlessly into one another.

[0032] This creates a cam arrangement in the form of a single cam, which defines different cam contours along its axial extent.

[0033] It is particularly advantageous if the cam assembly is mounted axially displaceable on the camshaft and the adjusting device is designed to move the cam assembly along the camshaft in order to allow one of the cam contours to act on the adjusting element at any given time.

[0034] The cam arrangement is preferably mounted axially displaceable on the camshaft, but positively connected to it in the direction of rotation, for example via a keyway profile or the like.

[0035] It is particularly advantageous if the adjustment device has an electromechanical linear drive.

[0036] Such a linear drive can be implemented using an electromagnetic actuator, an electric motor, or the like.

[0037] However, it is also generally conceivable that the adjustment device is pneumatically or hydraulically driven.

[0038] The electromechanical linear drive preferably has a variable displacement electric motor, the rotation of which is converted into a translational movement of the cam assembly relative to the camshaft via a variable displacement converter.

[0039] The adjusting electric motor can preferably be arranged parallel to the main electric motor on a housing of the actuating arrangement.

[0040] The variable displacement converter is coupled to the cam assembly. Preferably, the variable displacement converter has a parallel guide or the like to ensure smooth movement of the cam assembly on the camshaft.

[0041] It is particularly advantageous if the variable speed converter is a spindle drive with a spindle driven by the variable speed electric motor and with a spindle nut connected to the cam assembly.

[0042] This allows the variable-speed converter to be implemented in a structurally advantageous arrangement parallel to the camshaft.

[0043] Overall, it is preferred if the camshaft has a closing rotation position corresponding to a valve closing position (preferably independent of the selected cam contour), wherein the main electric motor is configured to rotate the camshaft into the closing rotation position using an energy storage device when the main electric motor is disconnected from a regular power supply.

[0044] In other words, the main electric motor's control unit is configured to switch to auxiliary power from the energy storage device (e.g., supercapacitors) when the regular power supply is disconnected. This allows the relatively small amount of energy from the storage device to drive the main electric motor at least enough to bring the camshaft into the closing position. This prevents the unintentional leakage of fluids from the valve.

[0045] The closing rotation position can preferably be detected by means of a sensor.

[0046] The sensor preferably includes a Hall sensor that is precisely tuned to the closing rotation position, so that the closing rotation position can be reliably adjusted.

[0047] According to a further overall preferred embodiment, the adjusting element is coupled with a short-term actuator, by means of which the valve can be opened briefly, independent of the rotational position of the camshaft.

[0048] Using such a short-term actuator, short, individual spray bursts can be achieved, as required, for example, for a spot spray function. A short-time actuator is preferably an electromagnetic actuator, so that it can open the valve for a relatively short time for a few cycles with a very short switching time.

[0049] The momentary actuator is preferably not in use during camshaft operation. If the spot-spray function is required, the camshaft drive is interrupted. To activate the spot-spray function, the electromagnetic momentary actuator is energized. Depending on the actuator's design, its plunger extends or retracts and actuates the valve actuator. The valve actuator can be actuated perpendicular to its longitudinal axis, parallel to it, or at another angle, for example, using an actuating wedge directly connected to the valve actuator.

[0050] Furthermore, it is generally advantageous if the valve actuator is a second side of a two-sided lever, on the first side of which a valve seal is fixed and on the second side of which the cam arrangement engages.

[0051] In this design, suitable actuation of the valve with appropriate actuating forces can be advantageously arranged. Furthermore, it is possible to pre-tension the valve actuator towards a closed position by means of a spring arrangement, so that the cam arrangement deflects the valve actuator against the force of such a spring arrangement in order to open the valve.

[0052] According to a further preferred embodiment, an actuating roller is rotatably mounted on the valve actuator, on which the cam arrangement engages.

[0053] This can reduce friction losses.

[0054] Overall, it is preferred if the valve actuator is biased into a position relative to a housing (for example, by means of the spring arrangement mentioned above) in order to close the valve.

[0055] According to a further overall preferred embodiment, the main electric motor and / or the adjusting electric motor of the adjusting device is a brushless DC motor controlled by power electronics.

[0056] The speed of the DC motor is preferably controlled by means of the power electronics.

[0057] Furthermore, it is advantageous if the power electronics or an associated part of a control system has at least one electrical energy storage device that can provide sufficient energy to safely close the valve in the event of a power supply failure.

[0058] The energy storage device can be a rechargeable battery or a primary cell. Preferably, the energy storage device is a supercapacitor (so-called "SuperCap").

[0059] Furthermore, it is generally advantageous if the speed and / or rotational position of the electric motor is detected by means of a first speed sensor and / or if the speed and / or rotational position of the camshaft is detected by means of a rotation sensor.

[0060] For example, by measuring the speed of the camshaft, it is possible to control the speed of the electric motor.

[0061] Furthermore, it is generally advantageous if an adjustment sensor is designed to detect an adjustment position of the adjustment device.

[0062] This ensures that the adjustment position is set correctly. For example, it can be verified that a selected cam profile is actually set.

[0063] The above-mentioned plant treatment application device preferably has a plurality of valve arrangements which are arranged on a valve bar of a field sprayer and each equipped with a nozzle for applying plant treatment products. are connected. The valve arrangements are preferably controllable independently of each other.

[0064] In this method of applying plant protection products, the application rate can be regulated depending on the driving speed. Furthermore, the application rate can be regulated depending on other parameters such as plant height, density and / or spread, or depending on the steering angle of a tractor.

[0065] The plant treatment product can be, for example, a pesticide, but it can also be a liquid fertilizer.

[0066] The inventive method makes it possible to apply such plant treatment agents homogeneously in the same concentration over a large area, while also compensating for acceleration and deceleration during cornering.

[0067] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0068] Exemplary embodiments of the invention are shown in the drawing and are explained in more detail in the following description. They show: Fig. 1 shows a schematic view of an agricultural vehicle with a field sprayer driving across a planting area; Fig. 2 is a schematic representation of detail II of Fig. 1; Fig. 3 shows a schematic representation of an example of a valve arrangement with an electromechanical actuator and a flap valve; Fig. 4 shows a time sequence diagram of revolutions U of a rotary element (camshaft) of a rotary-translation converter with associated closing and opening positions of the valve due to different cam contours; Fig. 5 shows a perspective view of another embodiment of an actuating arrangement according to a further embodiment from an oblique front view; Fig. 6 is a perspective view of the actuation arrangement of Fig. 5 from a rear oblique angle; Fig. 7 shows a side view of the actuation arrangement of Figs. 5 and 6; Fig. 8 shows a top view of the actuation arrangement of Figs. 5 and 6; Fig. 9 shows a longitudinal view of the actuation arrangement of Figs. 5 and 6; Fig. 10 shows a sectional view along a line XX in Fig. 7; Fig. 11 shows a perspective sectional view of the actuation arrangement of Figs. 5 and 6, corresponding to Fig. 10; Fig. 12 shows a schematic representation of another embodiment of an actuating arrangement; Fig. 13 shows a schematic representation of a cam arrangement with two cam contours that transition seamlessly into one another; Fig. 14 shows a side view of another embodiment of a cam arrangement with five continuously transitioning cam contours; Fig. 15 Sectional views of the five cam contours of the cam arrangement of Figure 14; and Fig. 16 shows a flowchart of the valve lift versus the period of the camshaft revolutions for the five cam contours of the cam arrangement of Figure 14.

[0069] Fig. 1 schematically shows a planting area with a plurality of plants 12, which are planted, for example, in a certain row spacing 13, with driving lanes 14 being formed between them.

[0070] A crop treatment device 16 includes, for example, a tractor 18 or another agricultural vehicle to which a crop treatment application device 20 is attached. The crop treatment application device 20 includes a field sprayer 22. The field sprayer 22 has a valve bar 24 extending transversely to the direction of travel, to which a plurality of, for example, 20 to 200 nozzles 26 are attached. The nozzles 26 can be slidably mounted on the valve bar 24, but can also be rigidly attached to it.

[0071] A plant treatment product 28 can be applied to the plants 12 of the planting area 10 via the nozzles 26.

[0072] Fig. 2 shows a detail view II of Fig. 1.

[0073] It can be seen that a valve arrangement 30 is assigned to a nozzle 26 of the valve bar 24.

[0074] The valve arrangement 30 includes a valve 32, which is configured here as a 4 / 2-way valve. In particular, the valve 32 can be configured as a butterfly valve, as described below.

[0075] The valve 32 is actuated by means of an electric motor 34, which influences the valve 32 via a rotary-translational converter 36 in order to move it back and forth between the two positions.

[0076] The electric motor 34 and the rotary-translation converter 36 can be part of an actuating arrangement 38. The rotary-translation converter 36 is adjustable, as indicated by an arrow, to change a valve opening angle range per revolution of a rotary element of the rotary-translation converter or the electric motor 34 and / or an opening speed and / or a closing speed of the valve 32.

[0077] Fig. 3 shows an example of a valve arrangement 30 with such an actuating arrangement 38.

[0078] The valve 32 includes a valve control lever 40, which can be moved like a flap between a first valve position 42 (closed position) and a second valve position 44 (open position). The valve 32 also includes an inlet port 48 through which plant treatment agent 28 can be supplied. In the first valve position 42, the flow of the plant treatment agent 28 is interrupted. In the second valve position 44, the plant treatment agent 28 can flow to an outlet port 46 and a nozzle 26 connected thereto.

[0079] A sealing element 50 is fixed to the valve control lever 40. In the first valve position 42, the sealing element 50 rests against a valve seat (not otherwise specified) and consequently closes the valve. In this case, the valve seat against which the sealing element 50 rests is located on the downstream side adjacent to the outlet port 46. Alternatively, this valve seat can also be located on the upstream side.

[0080] The valve actuating lever 40 is pivotable about a bearing 52, which forms a pivot axis fixed to the housing. The valve actuating lever 40 is preferably designed as a two-sided lever, with one end of the lever being connected to the sealing element 50. The other The lever end is preferably arranged outside a housing 54 of the valve 32 and forms a valve actuator 60 of the valve 32.

[0081] In Fig. 3, the first valve position 42 is represented by a solid line of the valve actuating lever 40. The second valve position 44 is represented by dashed lines. The actuating arrangement 38 is biased into the first valve position 42 by means of a spring arrangement 62 that acts on the valve actuator 60.

[0082] The actuating arrangement 38 further includes, as part of the rotary-translation converter 36, a camshaft 70 which is operatively connected to the electric motor 34 via a schematically indicated gear arrangement 72 (e.g., a single- or multi-stage spur gear set) and rotates at a speed proportional to the speed of the electric motor 34. Alternatively, the electric motor 34 can also be directly connected to the camshaft 70.

[0083] A cam assembly 74 is arranged on the camshaft 70, on which a plurality of at least two cam contours N1, N2 are formed. The cam contours each extend by 360°.

[0084] The cam contours N1 and N2 can be alternatively aligned with the valve actuator 60 by means of an adjusting device 78 of the rotation-translation converter 36, so that one of the cam contours N1 or N2 acts on the valve actuator 60 at any given time. An adjusting sensor 76 is designed to detect the position of the adjusting device 78. This allows it to be determined which of the cam contours N1 or N2 acts on the valve actuator 60.

[0085] The cam contours N1 and N2 each have at least one opening section N1a and at least one closing section N1b. For example, cam contour N1 has an opening section N1a extending over approximately 340° and a closing section N1b extending over approximately 20°. Cam contour N2 has, for example, an opening section N2a extending over approximately 300° and a closing section N2b extending over approximately 60°. When an opening section N1b or N2b is in contact with the valve actuator 60, the valve actuator 60 is deflected against the force of the spring assembly 62, such that the first side of the valve lever The valve 32 is moved from the first valve position 42 to the second valve position 44, i.e., the valve 32 is open. If a closing section N1a or N1b is in contact with the valve actuator 60, as shown in Figure 3, the valve actuator 60 is not deflected. Consequently, the sealing element 50 is pressed against the valve seat of the valve 32 by the preload force of the spring assembly 62 to establish the first valve position 42.

[0086] The cam contours N1 and N2 act on the second side of the valve control lever 40, i.e., on the valve actuator 60. In Figure 3, for example, the first cam contour N1 acts on the valve actuator 60. The second cam contour N2 is arranged axially adjacent to the first cam contour N1 along the camshaft 70, i.e., behind the plane of the drawing in Figure 3.

[0087] When the electric motor 34 is set in rotation, the opening and closing angles of the valve 32 are as shown in Figure 4. The opening and closing angles, which are established by the cam profiles N1 and N2, are proportional to the opening and closing times of the valve 32, which in turn depend on the rotational speed of the electric motor 34. When cam profile N1 acts on the valve actuator 60, a valve opening angle range (corresponding to a second valve position 44) of 340° and a valve closing angle (corresponding to a first valve position 42) of 20° result per 360° revolution U of the camshaft 70. Conversely, when cam profile N2 acts on the valve actuator 60, a valve opening angle range of 300° and a valve closing angle of 60° result per revolution of the camshaft 70. It is understood that these valve opening angle ranges and valve closing angles are merely examples.For example, the valve opening angle range can always be larger than the valve closing angle.

[0088] The cam contours N1 and N2 shown in Figure 3, and the resulting valve opening angle range and valve closing angle shown in Figure 4, are selected such that the valve closing angles of cam contours N1 and N2 do not overlap. This representation was chosen for the purpose of better explanation. In practice, the valve closing angles of cam contours N1 and N2 will generally overlap.

[0089] Figures 5 to 11 show another embodiment of an actuating arrangement 38. In terms of its construction and function, this generally corresponds to the actuating arrangement 38 of Figure 3. Identical elements are therefore identified by the same reference numerals. The differences are explained in detail below.

[0090] The actuating arrangement 38 includes a box-like housing to which a valve 32 is attached. An upper surface of the valve 32 is connected to a valve bar receptacle 80. The plant treatment agent 28 or another fluid can be introduced into the inlet port 48 of the valve 32 via the valve bar receptacle 80. The valve bar receptacle 80 can be opened or closed, as shown schematically, to accommodate or remove a valve bar 24.

[0091] The adjusting device 78 includes an adjusting electric motor 82, which is arranged parallel and offset to the main electric motor 34. The adjusting electric motor 82 is connected to a spindle drive 84, which has a spindle 86 and a spindle nut 88. The spindle 86 is aligned parallel to the camshaft 70.

[0092] The spindle nut 88 is rigidly connected to a driver 90, which is axially displaceable via a parallel guide 92. The driver 90 is rigidly connected to the cam assembly 74, on which at least two different cam contours N1, N2 are formed axially offset.

[0093] The adjustable electric motor 82 and the spindle drive 84 together form an electric linear drive 93 for the driver 90.

[0094] By driving the adjusting electric motor 82, it is possible to align each of the cam contours N1, N2 with the valve actuator 60. The valve actuator 60 is formed by one side of a two-sided lever 40, which extends transversely, in particular obliquely, to the longitudinal axis of the camshaft 70 in one direction.

[0095] A longitudinal axis of the valve 32 between the inlet port 48 and the outlet port 46 intersects the axis of the two-sided lever 40 and is also skew to the axis of the camshaft 70.

[0096] To reliably determine that a cam contour N1, N2 selected by a higher-level control system is actually set, an adjustment sensor 76 is provided to detect the position of the driver 90. In this case, the adjustment sensor 76 is arranged in the area of ​​the parallel guide 92. Detection can be direct or indirect, either by detecting the position of the spindle nut 88 or by detecting the revolutions of the adjustment electric motor 82.

[0097] The main electric motor 94 is operatively connected to the camshaft 70 via a gear arrangement 72 in the form of a spur gear set. A sensor wheel 96 is fixed axially adjacent to an output shaft of the main electric motor 34 on the camshaft 70, on which a toothing of the gear arrangement 72 is formed and on which a magnet 98 is fixed at a specific circumferential position.

[0098] A circuit board 99 is mounted on the housing 56, and a sensor 94 is mounted on this board. The sensor 94 can be configured as a Hall sensor, so that it is set up to detect the rotational position of the sensor wheel 96, and thus of the camshaft 70, as defined by the magnet 98. The rotational position of the camshaft detectable by the sensor 94 and the magnet 98 is a closing rotational position, which corresponds to a closing position 42 of the valve 32.

[0099] To ensure that the valve 32 closes reliably even if a regular power supply is interrupted, the actuating arrangement 38 includes an energy storage device 100, for example in the form of a battery or a supercapacitor 100. The energy storage device 100 can also be integrated into the circuit board 99.

[0100] Furthermore, power electronics 102 can be provided on the circuit board or directly on the main electric motor 34.

[0101] When the regular power supply is interrupted, a control device (not shown in detail) is designed to use energy from the energy storage device 100 to control the main electric motor 34 by means of the power electronics 102 so that the camshaft is rotated into the closing position, which can be detected by the sensor 94 by detecting the position of the magnet 98.

[0102] The actuating arrangement 38 can optionally include a momentary actuator 104, as shown schematically in Fig. 10. The momentary actuator 104 is coupled to the valve actuator 60. When the actuation of the valve actuator by means of the camshaft 70 is deactivated and the valve 32 is in the closed position 42 (in which the sealing element 50 presses against the valve seat, which is connected to the outlet port 46), the momentary actuator 104 can be activated by energizing it to deflect the valve actuator 60 so that the valve 32 is moved into the open position 44. The momentary actuator is preferably an electromagnetic actuator that can open the valve 32 very quickly and briefly for a short time to establish a so-called spot-spray function. As mentioned, this is generally established when the camshaft 70 is stationary.

[0103] Figure 10 schematically shows that the short-time actuator 104 can pull downwards an armature (not shown) coupled to the valve actuator 60 in order to actuate the valve actuator 60. During operation of the camshaft, the short-time actuator 104 can remain de-energized, so that the armature can be moved without drag losses.

[0104] As an alternative to this configuration, it is also possible to configure the momentary actuator 104 such that the valve actuator 60 is pressed downwards by means of an armature (instead of the pulling movement shown in Fig. 10). According to a further alternative embodiment, a wedge can be formed on the valve actuator 60, against which an armature of an electromagnetic actuator 204 acts to actuate the valve actuator 60. For the sake of clarity, the momentary actuator 104 is not shown in Fig. 11.

[0105] Figures 10 and 11 also show an actuating roller 106, which is rotatably mounted on the valve actuator 60 and on which a cam contour N1, N2 acts as engaged. This reduces friction losses when the cam arrangement 74 engages the valve actuator 60.

[0106] Figure 12 shows an alternative embodiment of an actuating arrangement 38A, which generally corresponds to the actuating arrangements described above in terms of its construction and function. Identical elements are therefore identified by the same reference numerals. The differences are explained in detail below.

[0107] In the actuating arrangement 38A, a main electric motor 34A is rotationally fixed to a camshaft 70A, on which different cam contours N1, N2, N3 are formed. The arrangement consisting of the main electric motor 34A and the camshaft 70A, on which a cam assembly 74A is arranged, can be adjusted axially as a whole by means of an adjusting electric motor 82A, which adjusts the arrangement via a spindle drive (not shown) in order to selectively align one of the cam contours N1, N2, N3 with the valve actuator 60A.

[0108] In general, the cam contours R1, R2, R3 can be axially offset from each other and / or transition into each other with steps.

[0109] However, it is preferred, as shown in Fig. 13, if the cam arrangements 74, 74A described above are formed by a cam arrangement 74B with a single cam in which the cam contours NT, N2' transition smoothly into one another.

[0110] Figures 14 and 15 show another cam arrangement 74C in a side view on a camshaft 70 and in sectional views, respectively. The cam arrangement 74C comprises five different cam contours N1, N2, N3, N4, and N5.

[0111] The N1 cam profile establishes a valve opening angle range of 100%, i.e., an angle range of 360° per revolution of the camshaft 70. The N1 cam profile establishes a valve opening angle range of 100%, i.e., an angle range of 360° per Camshaft 70 revolutions. Cam contour N2 establishes a valve opening angle range of 75%, i.e., an angle range of 270° per revolution of camshaft 70. Cam contour N3 establishes a valve opening angle range of 50%, i.e., an angle range of 180° per revolution of camshaft 70. Cam contour N4 establishes a valve opening angle range of 25%, i.e., an angle range of 90° per revolution of camshaft 70. Cam contour N5 establishes a valve opening angle range of 0%, i.e., an angle range of 0° per revolution of camshaft 70. Cam contour N5 corresponds to a permanent closed position of valve 32.

[0112] Figure 16 shows the valve lift of the flap of the flap valve 32 for two periods, i.e. for two revolutions of the camshaft 110, for the five different cam contours N1, N2, N3, N4, N5 corresponding to the valve opening angle ranges of 360° (100%), 270° (75%), 180° (50%), 90° (25%), and 0° (0%).

[0113] In the cam arrangement 74C, the five cam contours N1, N2, N3, N4, N5, which are arranged adjacent to each other in this order in the axial direction, also transition seamlessly into one another.

[0114] The sectional views of Figure 15 further show that the cam assembly 74 C is axially displaceable on the camshaft 70 and is positively connected to the camshaft 70 in the circumferential direction by means of a keyway profile shown in Figure 15, but not further specified. Reference symbol list: 10 planting area 12 plants 14 lanes 16 Plant treatment device 18 tractor 20 Plant treatment product application device 22 field sprayers 24 valve strip 26 nozzles 28 plant treatment products 30 Valve arrangement 32 valve, 4 / 2-way valve (flap valve) 34 Electric motor 36 Rotational / Translational Converters 38 Actuation arrangement 40 Valve actuating levers (flap) 42 first valve position (closed) 44 second valve position (open) 46 Outlet connection (drain) 48 Inlet connection 50 sealing elements 52 warehouses 54 Valve housings 56 Actuator assembly housing 60 Valve actuator (second side of valve control lever) 62 Spring arrangement 70 Camshaft 72 Gear arrangement (34 / 70) 74 Cam arrangement 76 Adjustment sensor 78 Adjustment device 80 Valve rail mount 82 Adjustable electric motor 84 Spindle drive 86 spindle 88 Spindle nut 90 drive lugs (88 / 74) 92 Parallel guidance 93 electric linear actuator 94 Sensor (Hall sensor) 96 Sensor wheel (70) 98 Magnet 99 circuit board 100 energy storage devices (SuperCap) 102 Power Electronics 104 Short-term actuator 106 Actuating roller N1 first cam contour N1a Opening section N1b Closing section N2 second cam contour N2a Opening section N2b locking section N3 third cam contour N4 fourth cam contour N5 fifth cam contour

Claims

Patent claims 1. Actuating arrangement (38) for actuating a valve (32), in particular a valve (32) of a plant treatment application device (20) by means of a main electric motor (34), characterized in that the main electric motor (34) is coupled to a valve actuator (60) of the valve (32) by means of a rotary-translation converter (36) in order to open and close the valve (32) at least once and at least once with each revolution of a rotary element (70) of the rotary-translation converter (36) in order to establish a valve opening angle range per revolution, wherein the rotary-translation converter (36) is adjustable by means of an adjusting device (78) in order to change the valve opening angle range per revolution and / or an opening speed and / or a closing speed.

2. Actuating arrangement according to claim 1, wherein the rotation-translation converter (36) has a camshaft (70) driven by the main electric motor (34) with a cam assembly (74) arranged thereon which acts on the adjusting element (60), wherein the cam assembly (74) has at least two different cam contours (N1, N2) which define different valve opening angle ranges per revolution and / or different opening speeds and / or different closing speeds, wherein the adjusting device (78) is configured to set up one of the cam contours (N1, N2) to act on the adjusting element (60).

3. Actuating arrangement according to claim 2, wherein the different cam contours (N1 , N2) are arranged adjacent to each other along a longitudinal axis of the camshaft (70) and preferably transition continuously or steplessly into one another. Actuating arrangement according to claim 3, wherein the cam arrangement (74) is axially displaceable on the camshaft (70) and the adjusting device (78) is designed to displace the cam arrangement (74) along the camshaft (70) in order to allow one of the cam contours (N1, N2) to act on the adjusting element (60).

5. Actuating arrangement according to one of claims 2 to 4, wherein the adjusting device (78) has an electromechanical linear drive (93).

6. Actuating arrangement according to claim 5, wherein the electromechanical linear drive (93) has a variable displacement electric motor (82) whose rotation is converted via a variable displacement converter (86, 88) into a translational movement of the cam assembly (74) with respect to the camshaft (70), wherein the variable displacement converter is preferably a spindle drive with a spindle (86) driven by the variable displacement electric motor (82) and with a spindle nut (88) connected to the cam assembly (74).

7. Actuating arrangement according to one of claims 2 to 6, wherein the camshaft (70) has a closing rotary position corresponding to a closing position (42) of the valve (32), and wherein the main electric motor (34) rotates the camshaft (70) into the closing rotary position using an energy storage device (100) when the main electric motor (34) is disconnected from a regular power supply, wherein the closing rotary position is preferably detectable by means of a sensor (94).

8. Actuating arrangement according to one of claims 2 to 7, wherein the adjusting element (60) is coupled to a short-time actuator (104) by means of which the valve (32) can be opened briefly independently of the rotational position of the camshaft (70).

9. Actuation arrangement according to one of claims 2 to 8, wherein - the valve actuator (60) is a second side of a two-sided lever (40), on the first side of which a valve seal (50) is fixed and on the second side of which the cam assembly (74) engages, and / or - an actuating roller (106) is rotatably mounted on the valve actuator (60), on which the cam assembly (74) engages.

10. Actuating arrangement according to any one of claims 1 to 9, wherein the valve actuator (60) is biased relative to a housing (56) in a position to close the valve (32).

11. Actuating arrangement according to one of claims 1 to 10, wherein the main electric motor (34) and / or an adjusting electric motor (82) of the adjusting device (78) is a brushless DC motor controlled by a power electronics (102).

12. Actuating arrangement according to claim 11, wherein the power electronics (102) has at least one electrical energy storage device (100) which can provide sufficient energy in the event of a power supply failure to safely close the valve (32).

13. Actuating arrangement according to one of claims 1 to 12, wherein a rotation sensor (94) is configured to detect a rotational speed and / or a rotational position of the camshaft (70) and / or an adjustment sensor (76) is configured to detect an adjustment position of the adjustment device (78).

14. Valve arrangement (30) comprising a flap valve (32) and an actuating arrangement (38) according to one of claims 1 to 13.

15. Plant treatment product application device (20) with at least one valve arrangement (30) according to claim 14.

16. Plant treatment product application device according to claim 15, comprising a plurality of valve arrangements (30) arranged on a valve bar (24) of a field sprayer (22) and each connected to a nozzle (26) for applying plant treatment product (28).

7. Method for applying plant protection products by means of a plant protection product application device (20) according to claim 15 or 16, comprising the step of controlling an application quantity during a traversal of a planting area (10) as a function of a driving speed and / or another parameter by actuating the valve (32) of the valve arrangement (30).

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