Patent Application
20250019913
This application claims foreign priority benefits under 35 U.S.C. § 119 (a)-(d) to European patent application number 23185510.7 filed Jul. 14, 2023, which is incorporated by reference in its entirety.
The present disclosure relates to the technical field of road pavers. In particular, the disclosure relates to road pavers with a screed for compacting paving material and methods for controlling such road pavers.
From DE 102021107447 A1, a method for determining a change in an attack angle of a screed is known. DE 19647150 A1 shows a method for controlling the screed height of a screed. From EP 2366831 B1, a method for controlling the paving thickness and quality of bituminous paving material is known.
In leveling feedback controls known from the prior art, a screed height of the screed is detected and adjusted with the help of a leveling cylinder. During paving, a screed lifting cylinder is usually in the floating position. In order to influence the static compaction, a constant pressure may be set on the rod side of the screed lifting cylinder. The underside of the screed has an inclination to the subgrade. This inclination is referred to as the attack angle and is adjusted to a predefined value at the beginning, among others by the screed lifting cylinder. The attack angle influences the quality of the paving result, in particular the compaction of the paving material and the resulting surface appearance. A constant attack angle during operation is therefore advantageous.
A change in screed height, a change in the installation speed of the road paver and/or a change in paving material may effect a change in the attack angle of the screed. An attack angle that is too large or too small may lead to a poor paving result. Particularly with road pavers with extension screeds, an undesirable attack angle may lead to different screed heights between the base screed and the extension parts, resulting in unevenness in the transverse direction of the road.
In the systems known from the prior art, only the screed height is continuously adjusted by adjusting the leveling cylinder. However, this means that the attack angle is not constant, but results from the current position of the leveling cylinder as well as the paving material properties and other environmental conditions. The attack angle is geometrically defined by the position of the leveling cylinder and the layer thickness.
A goal of the present disclosure is to keep the attack angle of the screed as constant as possible during operation and thus improve the paving quality.
This object is solved by a road paver according to the disclosure, a method for feedback controlling a position of a screed assembly according to the disclosure or a use of a feedback control device according to the disclosure.
The paving result may be significantly improved by embodiments according to the present disclosure. By continuously checking and adjusting the attack angle of the screed assembly, the longitudinal evenness of the paved material may be improved. When using extension screeds, the transverse evenness of the paved material may also be improved by embodiments according to the present disclosure. In addition, the compaction result may be improved by a constant attack angle. Process reliability may also be increased with embodiments according to the present disclosure, as no manual monitoring or manual readjustment of the attack angle is necessary. The system may react automatically to changes in the paving material, which reduces paving errors.
A first aspect of the disclosure relates to a road paver with a towing vehicle, at least one tow arm, a screed assembly, a leveling cylinder, a screed lifting cylinder, a first measuring device, a second measuring device and a feedback control device. The screed assembly is attached to a tow point of the towing vehicle via the at least one tow arm. The leveling cylinder is adapted to adjust a position, in particular the height, of the tow point. The screed lifting cylinder is adapted to adjust the contact pressure of the screed assembly. The contact pressure refers to the pressure that the screed assembly exerts on the paving material, in particular due to its dead weight. The contact pressure of the screed assembly may result from the dead weight of the screed assembly and the forces from the screed lifting cylinder. The forces from the screed lifting cylinder may have a loading or unloading effect. The first measuring device is adapted to determine the screed height of the screed assembly. The second measuring device is adapted to determine an attack angle of the screed assembly. The feedback control device is adapted to control the leveling cylinder and the screed lifting cylinder.
The screed assembly may be configured to form a road paver together with a towing vehicle. The screed assembly may be attached to the towing vehicle. The screed assembly may be configured to be towed behind the towing vehicle in the paving direction. The screed assembly may be configured to compact paving material, in particular bituminous paving material, on a subgrade. The screed assembly may be configured to plane paving material, in particular bituminous paving material, on a subgrade.
A transverse direction is defined as a direction that extends in a horizontal plane and is perpendicular to the paving direction. The paving direction is the direction in which the road paver moves during paving. A lateral direction or a width direction may be a direction parallel to the transverse direction.
The screed assembly may comprise a base screed and at least one extension part, preferably two extension parts. The base screed is also referred to as the main screed in the context of the disclosure. The extension part is also referred to as a secondary screed in the context of the disclosure. The extension parts may be arranged laterally, in the transverse direction, to the left and right of the base screed. The extension parts may be arranged behind the base screed in the paving direction. Alternatively, the extension parts may be arranged in front of the base screed in the paving direction.
The base screed may comprise a base screed planing sheet for contact with the paving material. The extension part may comprise a planing sheet support and an extension part planing sheet. The extension part planing sheet may be configured to contact the paving material. The extension part planing sheet may be attached to the planing sheet support so as to be tiltable about a tilting axis. The screed assembly may comprise a height adjustment device. The screed assembly may comprise a tilting device. The height adjustment device may be adapted to lower or raise the extension part or parts relative to the base screed. The height adjustment device may be configured to lower or raise the planing sheet support relative to the base screed. The tilting device may be configured to change a tilting angle of the extension part planing sheet about the tilting axis. The tilting axis may extend in a transverse direction. The tilting axis may extend horizontally.
The screed height of the screed assembly may denote the vertical distance between a rear edge of the screed assembly, in particular a rear edge of a planing sheet of the screed assembly, and a reference point, for example on the subgrade. The screed height of the base screed may denote the vertical distance between a rear edge of the base screed, in particular a rear edge of the base screed planing sheet, and a reference point, for example on the subgrade. The screed height of the extension part may denote the vertical distance between a rear edge of the extension part, in particular a rear edge of the extension part planing sheet, and a reference point, for example on the subgrade. The term rear edge refers to the rearmost edge of the base screed or extension part in the paving direction. The height of the rear edge or the screed height determines the installation height of the paving material.
The attack angle of the screed assembly may denote the inclination of the screed assembly, in particular of a planing sheet of the screed assembly, relative to the inclination of the subgrade. In the case of a horizontal subgrade, the attack angle of the screed assembly corresponds to the absolute inclination of the planing sheet. The term “absolute inclination” indicates that the inclination is determined in relation to a horizontal plane. In the case of an inclined subgrade, the attack angle corresponds to the difference between the absolute inclination of the planing sheet and the absolute inclination of the subgrade.
The attack angle of the base screed may denote the inclination of the base screed, in particular the base screed planing sheet, relative to the inclination of the subgrade. The attack angle of the extension part may denote the inclination of the extension part, in particular of the extension part planing sheet, relative to the inclination of the subgrade.
The screed assembly may be rotatably attached to a tow point of the road paver, in particular of a towing vehicle of the road paver, via at least one tow arm. The screed assembly may be rotatably attached to the tow point of the road paver, in particular of the towing vehicle, via two tow arms. The tow arms may be arranged on the side of the towing vehicle. One tow arm may be arranged on each side of the towing vehicle. The height of the tow point may be adjusted using a leveling cylinder. The road paver may have two tow arms and two leveling cylinders. Each leveling cylinder may be assigned to a tow arm. The leveling cylinders may be connected to the respective tow arm. The connection between the leveling cylinder and tow arm may occur directly or via an intermediate piece. The leveling cylinders and the tow arms may be arranged laterally with respect to the transverse direction on the road paver. The road paver may have a tow arm and a leveling cylinder on each side. The features described in the further course of this application in connection with the leveling cylinder also relate to both leveling cylinders, even if this is not explicitly mentioned.
The screed assembly, in particular the base screed, may be connected to the towing vehicle by a screed lifting cylinder. The screed assembly, in particular the base screed, may be connected to the towing vehicle by two screed lifting cylinders. The screed lifting cylinder or screed lifting cylinders may be used to raise or lower the screed assembly vertically. The screed lifting cylinder or screed lifting cylinders may be used to adjust the contact pressure of the screed assembly on the paving material. The features described below in connection with the screed lifting cylinder also apply to both screed lifting cylinders, even if this is not explicitly mentioned.
The screed lifting cylinder may be connected directly to the screed assembly or base screed. The screed lifting cylinder may be indirectly connected to the screed assembly or base screed. The screed lifting cylinder may be attached to the tow arm, in particular a rear area of the tow arm.
The road paver may have a material hopper. The material hopper may be adapted to receive paving material. The material hopper may be arranged in front of the screed assembly in the paving direction.
The road paver may have a control device. The control device may be adapted to control the screed lifting cylinder. The control device may be adapted to control the leveling cylinder. The control device may be adapted to control the screed lifting cylinder and the leveling cylinder. The control device may be part of the feedback control device.
The feedback control device may have a first controller. The first controller may be adapted to control the leveling cylinder or the leveling cylinders based on a control deviation of the screed height. The control deviation of the screed height is the difference between a target value of the screed height, for example the desired installation height, and the actual value of the screed height. The control deviation of the screed height may be determined from the target value of the screed height and the actual screed height determined by the first measuring device. The target value of the screed height may be specified by manual user input. The target value of the screed height may be specified or suggested by a control system, in particular depending on the paving material. The target value of the screed height may be determined based on stored values from previous construction measures. The target value of the screed height may be derived from the road construction plan. The target value of the screed height may be entered manually. The target value may be taken directly from digital planning data.
The feedback control device may have a second controller. The second controller may be adapted to control the screed lifting cylinder or the screed lifting cylinders based on a control deviation of the attack angle. The control deviation of the attack angle is the difference between a target value of the attack angle, for example the desired attack angle, and the actual value of the attack angle. The control deviation of the attack angle may be determined from the desired value of the attack angle and the actual attack angle determined by the second measuring device. The second controller may be adapted to calculate the required pressure in the screed lifting cylinder based on the determined actual attack angle. The target value of the attack angle may be specified by manual user input. The target value of the attack angle may be specified or suggested by a control system, in particular depending on the paving material. The target value of the attack angle may be determined based on stored values from previous construction measures. The target value of the attack angle may be selected to match the height setting of the extension part. This allows to adjust a good compaction, which may lead to a good paving pattern.
The feedback control device may have a first controller. The first controller may be adapted to control the leveling cylinder based on a control deviation of the screed height. The feedback control device may have a second controller. The second controller may be adapted to control the screed lifting cylinder also based on a control deviation of the screed height.
The first controller may be a SISO controller (single-input single-output controller), for example a P controller (proportional controller), a PI controller (proportional-integral controller) or a PID controller (proportional-integral-differential controller). The first controller may be a robust controller, for example an H-infinity controller. The second controller may be a SISO controller, for example a P-controller, a PI-controller or a PID-controller. The second controller may be a robust controller, for example an H-infinity controller.
The feedback control device may have a multi-variable controller. The multi-variable controller may be adapted to control the leveling cylinder and the screed lifting cylinder based on a control deviation of the screed height and a control deviation of the attack angle. Both feedback controlling variables, attack angle and screed height, may be controlled by one controller, the multi-variable controller. This allows interactions between the two controlled variables, attack angle and screed height, and the two actuating variables, leveling cylinder and screed lifting cylinder, to be taken into account. The multi-variable controller may also be referred to as a MIMO controller (multiple-input-multiple-output controller). The multi-variable controller may be an H-infinity controller, an LQ controller or an LQG controller.
In systems known in the prior art, the current installation speed is usually included in the feedback controlling. With the feedback control device according to the disclosure, this is not necessary. The feedback control device, in particular the multi-variable controller, may be adapted to output no other control variables apart from the attack angle and the screed height. The feedback control device, in particular the multi-variable controller, may be adapted to control the screed lifting cylinder and the leveling cylinder based solely on the attack angle and the screed height, in particular on a target/actual comparison of the attack angle and a target/actual comparison of the screed height. The feedback control device, in particular the multi-variable controller, may be adapted to control the screed lifting cylinder and the leveling cylinder exclusively based on measured values from the first measuring device and the second measuring device. The feedback control device, in particular the multi-variable controller, may be adapted to control the screed lifting cylinder and the leveling cylinder without taking the installation speed into account. The feedback control device may be adapted to select control parameters depending on the installation speed. The feedback control device may be adapted to control the screed lifting cylinder and the leveling cylinder depending on the installation speed. The feedback control device may be adapted to apply a large controller amplification at a high installation speed and a small controller amplification at a low installation speed. The terms high, low, large and small are to be understood in relation to each other.
The first measuring device may be a distance meter, for example a laser distance meter, a mechanical probe or an acoustic distance meter.
The second measuring device may have a first inclination sensor. The second measuring device may have a second inclination sensor. The second measuring device may have the first inclination sensor and the second inclination sensor. The first inclination sensor may be arranged on the screed assembly. The second inclination sensor may be arranged on the towing vehicle.
The first inclination sensor may be adapted to determine an inclination angle of the screed assembly relative to a horizontal plane. The second inclination sensor may be adapted to determine an inclination angle of the towing vehicle relative to the horizontal plane. The second measuring device may be adapted to determine the attack angle of the screed assembly from the inclination angle of the screed assembly and the inclination angle of the towing vehicle.
The first inclination sensor may be adapted to determine an inclination angle of the base screed relative to a horizontal plane. The first inclination sensor may be adapted to determine an inclination angle of the extension part relative to a horizontal plane. The inclination angle of the towing vehicle may correspond to the inclination of the subgrade. Alternatively, the inclination of the subgrade or the inclination angle of the towing vehicle may be determined from a digital terrain model. The second inclination sensor on the towing vehicle is not necessary in this case. The inclination angle may be calculated based on the measured inclination angle of the first inclination sensor and the inclination of the subgrade determined from the terrain model. Several first inclination sensors may be attached so that the inclination angle of the screed assembly is determined and controlled at several points, for example at two extension parts. Several second inclination sensors may be attached so that the inclination angle of the towing vehicle is determined from the average value of the second inclination sensors.
The second measuring device may have an inclination sensor attached to the base screed or the extension part. The inclination sensor may be configured to determine an inclination angle of the base screed or the extension part relative to a horizontal plane. A control device of the road paver may be adapted to determine a subgrade inclination based on a digital terrain model. The control device may be adapted to determine the attack angle of the base screed based on the determined inclination angle of the base screed and the subgrade inclination. The control device may be adapted to determine the attack angle of the extension part based on the determined inclination angle of the extension part and the subgrade inclination.
The second measuring device may have a rotational angle sensor. The rotational angle sensor may be arranged at the tow point of the towing vehicle. The rotational angle sensor may be adapted to measure the inclination of the tow arm relative to the inclination of the towing vehicle. The screed assembly may be rigidly connected to the tow arm. The attack angle of the screed assembly may then be determined via the inclination of the tow arm. The angle of rotation measured at the tow point may correspond to the attack angle.
The second measuring device may have a first rotational angle sensor on a first tow arm, which is attached to the side of the towing vehicle, and a second rotational angle sensor on a second tow arm, which is attached to the other side of the towing vehicle. The attack angle of the screed assembly may then be determined based on the average value of the first and second rotational angle sensors.
The feedback control device and/or the control device may be configured to filter environmental influences. The feedback control device and/or the control device may be configured to filter influences from vibration and/or temperature fluctuations. Advanced signal processing methods, such as Kalman filters or state observers, may be used for this purpose.
The screed assembly may have a base screed and at least one extension part. The extension part may be arranged at least partially offset from the base screed in the paving direction of the road paver. The extension part may be arranged at least partially in front of or behind the base screed in the paving direction of the road paver. The extension part may be arranged completely in front of or behind the base screed in the paving direction of the road paver. The base screed and the extension part may have the same attack angle. The extension part may be arranged laterally, in relation to the transverse direction, next to the base screed. The screed assembly may have two extension parts. The extension parts may be arranged on both sides of the base screed, with respect to the transverse direction. The extension parts may be laterally retractable and extendable so that the width of the screed assembly may be varied. The width of the screed assembly corresponds to the extension of the screed assembly in the transverse direction. The extension part may have a vertical offset relative to the base screed. The vertical offset may be adjusted by the height adjustment device. Due to the geometric arrangement of the base screed and extension part, the vertical offset is only optimal for a certain attack angle. If the attack angle changes, the vertical offset must be adjusted. Otherwise, the base screed and the extension part will have different screed heights. This may lead to imprints of the extension part in the installed layer and unevenness in the transverse direction. The screed assembly may also consist of a base screed only and have no extension parts.
The screed lifting cylinder may have a pressure control device on the piston side. The screed lifting cylinder may be adapted in such a way that it allows the screed assembly to be relieved and loaded. This allows both too small and too large attack angles to be corrected. The feedback control device may adjust the attack angle if it is too small or too large.
A second aspect of the disclosure relates to a method for feedback controlling a position of a screed assembly of a road paver. The screed assembly is attached to a tow point of the road paver, in particular by means of at least one tow arm. The method comprises determining a screed height of the screed assembly and determining an attack angle of the screed assembly. The method further comprises adjusting the position, in particular the height, of the tow point based on the determined screed height. The method further comprises adjusting a contact pressure of the screed assembly based on the determined attack angle.
Adjusting the position of the tow point may comprise adjusting the height, a vertical position, of the tow point.
Determining the screed height may occur continuously. Determining the attack angle may occur continuously. Determining the screed height may occur at the same time as determining the attack angle. Determining the screed height and/or the attack angle may occur at regular intervals.
Adjusting the position of the tow point may occur continuously. Adjusting the contact pressure may occur continuously. Adjusting the position of the tow point may occur at the same time as adjusting the contact pressure. Adjusting the position of the tow point and/or adjusting the contact pressure may occur at regular intervals.
Adjusting the position of the tow point may occur at a later time than adjusting the contact pressure. For example, the screed height may be determined first and the position of the tow point adjusted based on this. The attack angle may then be determined and the contact pressure adjusted based on this. The screed height may then be determined again and the position of the tow point adjusted. This iterative process may be repeated continuously.
Adjusting the position, in particular the height, of the tow point may occur during operation of the road paver, in particular during the installation of the paving material. Adjusting the contact pressure may occur during operation of the road paver, in particular during the installation of the paving material. Adjusting the position, in particular the height, of the tow point and adjusting the contact pressure may occur during the operation of the road paver, in particular during the installation of the paving material. During the installation of the paving material, the road paver moves in the paving direction.
Adjusting the position, in particular the height, of the tow point may occur automatically, in particular by a feedback control device or control device. Adjusting the contact pressure may occur automatically, in particular by a feedback control device or control device. Adjusting the position, in particular the height, of the tow point and adjusting the control device may occur automatically, in particular by a feedback control device or control device.
The determined screed height may be fed to a feedback control device or control device. The determined attack angle may be fed to a feedback control device or control device. The determined screed height and the determined attack angle may be fed to a feedback control device or control device.
The feedback control device may have a common multi-variable controller for feedback controlling the screed height and the attack angle. The multi-variable controller may be an H-infinity controller, an LQ controller (linear-quadratic controller) or an LQG controller.
The feedback control device may have two separate controllers. The feedback control device may have a first controller for feedback controlling the screed height. The feedback control device may have a second controller for feedback controlling the attack angle.
Adjusting the position, in particular the height, of the tow point may in addition be based on the determined attack angle. Adjusting the contact pressure of the screed assembly may in addition be based on the screed height determined.
Adjusting the position, in particular the height, of the tow point may occur by means of a leveling cylinder, in particular two leveling cylinders. The leveling cylinder may be attached to the road paver's towing vehicle and to the tow point. The position of the tow point may be changed by extending and retracting the leveling cylinder. The screed assembly may be attached to the tow point by means of a tow arm, in particular two tow arms. The screed height of the screed assembly may thus be changed by extending and retracting the leveling cylinder or the leveling cylinders.
Adjustment of the contact pressure of the screed assembly may occur by means of a screed lifting cylinder, in particular two screed lifting cylinders. The screed lifting cylinder may be attached to the screed assembly and to the road paver's towing vehicle. The pressure on the screed assembly may be varied by extending and retracting the screed lifting cylinder. A pressure control valve may be used to adjust, in particular regulate, the pressure in the screed lifting cylinder. The screed lifting cylinder may have a rod side and a piston side. The pressure control valve may be used to adjust, in particular regulate, the pressure on the rod side of the screed lifting cylinder. The screed lifting cylinder may be used to vary the pressure on the screed assembly. The pressure on the screed assembly may be varied using the pressure control valve. The screed lifting cylinder may be adapted to relieve and/or additionally load the screed assembly. The attack angle of the screed assembly may be adjusted by extending and retracting the screed lifting cylinder or screed lifting cylinders. A higher contact pressure may lead to a greater attack angle. Lower contact pressure may lead to a smaller attack angle.
The screed lifting cylinder may have a pressure control mechanism on the piston side. The pressure control mechanism on the piston side may be used to increase the attack angle.
A third aspect of the disclosure relates to the use of a feedback control device for feedback controlling an attack angle of a screed assembly of a road paver and for feedback controlling a screed height of the screed assembly.
The feedback control device may be adapted to perform feedback control of the attack angle and the screed height during operation of the road paver, in particular during the installation of the paving material. The feedback control may occur automatically. The feedback control may occur continuously. The feedback control may occur at regular intervals.
The feedback control device may be adapted to receive and process measured values from a first measuring device, which determines the screed height, and measured values from a second measuring device, which determines the attack angle. The feedback control device may perform feedback control based on the transmitted measured values of the screed height and the attack angle.
The feedback control device may be adapted to control a leveling cylinder, in particular two leveling cylinders. The leveling cylinder may change the position, in particular the height, of a tow arm connected to the screed assembly. The feedback control device may be adapted to change the screed height by controlling the leveling cylinder.
The feedback control device may be adapted to control a screed lifting cylinder, in particular two screed lifting cylinders. The screed lifting cylinder may change the contact pressure of the screed assembly on the paving material. The contact pressure may be used to adjust the attack angle of the screed assembly. The feedback control device may be adapted to change the contact pressure of the screed assembly by controlling the screed lifting cylinder, in particular the screed lifting cylinders. The feedback control device may be adapted to change the attack angle of the screed assembly by controlling the screed lifting cylinder, in particular the screed lifting cylinders.
The feedback control device may have a multi-variable controller. The multi-variable controller may be used for feedback controlling the attack angle of the screed assembly and for feedback controlling the screed height of the screed assembly. The multi-variable controller may be adapted to use the determined attack angle and the determined screed height as input parameters. The multi-variable controller may be adapted to control the leveling cylinder, in particular the leveling cylinders, and the screed lifting cylinder, in particular the screed lifting cylinders, in particular based on the determined screed height and the determined attack angle.
The feedback control device may have a first controller and a second controller. The first controller may be used for feedback controlling the screed height of the screed assembly. The second controller may be used for feedback controlling the attack angle of the screed assembly. The first controller may be used to control the leveling cylinder, in particular the leveling cylinders. The second controller may be used to control the screed lifting cylinder, in particular the screed lifting cylinders.
The road paver according to the first aspect of the disclosure may be used with method steps of the method according to the second aspect of the disclosure. The method according to the second aspect of the disclosure may be performed with a road paver according to the first aspect of the disclosure. The use of a feedback control device according to the third aspect of the disclosure may be performed with a road paver according to the first aspect of the disclosure and/or using method steps of the method according to the second aspect of the disclosure.
The expressions “first”, “second”, “third” and “fourth” are to be understood merely as determinations of a particular element or component and do not necessarily imply a particular order of said components or elements. For example, the presence of a second component does not necessarily imply the presence of a first component and vice versa.
The disclosure is explained in more detail below with reference to embodiments.
A leveling cylinder 8 is arranged on each side of the road paver 1. The leveling cylinder 8 is connected to the respective tow arm 4 via an intermediate piece 9. The position, in particular the height, of the tow points 5 may be adjusted using the leveling cylinders 8. Two screed lifting cylinders 10 are arranged in the rear area of the road paver 2. The screed lifting cylinders 10 are attached to a rear area of the respective tow arm 4. Alternatively, the screed lifting cylinders 10 may also be connected directly to the screed assembly 3. The screed lifting cylinders 10 may be used to adjust the position, in particular the height, and the contact pressure of the screed assembly 3.
As one skilled in the art would understand, the feedback control device 50, the first measuring device 59, the first controller 60, the second measuring device 61, the second controller 62, the multi-variable controller 63, as well an any other control system, unit, machine, apparatus, element, sensor, device, component, system, subsystem, arrangement, or the like described herein may individually, collectively, or in any combination comprise appropriate circuitry, such as one or more appropriately programmed processors (e.g. one or more microprocessors including central processing units (CPU)) and associated memory, which may include stored operating system software and/or application software executable by the processor(s) for controlling operation thereof and/or for performing the particular algorithms represented by the various functions and/or operations described herein, including interaction and/or cooperation between any such feedback control device, measuring device, controller, control system, unit, machine, apparatus, element, sensor, device, component, system, subsystem, arrangement, or the like. One or more of such processors, as well as other circuitry and/or hardware, may be included in a single ASIC (Application-Specific Integrated Circuitry), or several processors and various circuitry and/or hardware may be distributed among several separate components, whether individually packaged or assembled into a SoC (System-on-a-Chip).
| Number | Date | Country | Kind |
|---|---|---|---|
| 23185510.7 | Jul 2023 | EP | regional |
