Apparatus and method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment

Abstract

Provided is an apparatus for determining (406) a target rotational speed for a rotary drive (130) driving a displacement pump (125) of a hydraulic system of a lifting equipment (120). The apparatus includes processing circuitry (110) configured to receive first input data (101) indicating a target flow rate of hydraulic fluid to be provided by the displacement pump (125). Further, the processing circuitry (110) is configured to receive second input data (102) indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining (406) the target rotational speed. The processing circuitry (110) is configured to determine the target rotational speed based on the target flow rate according to the mode indicated by the user input. Additionally, the processing circuitry (110) is configured to output control data (103) indicating the determined target rotational speed.

Description

Field

[0001] The present disclosure relates to controlling rotary drives driving displacement pumps of lifting equipment. In particular, examples of the present disclosure relate to an apparatus and a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment, and a vehicle comprising the apparatus.Background

[0002] Cranes, in particular loader cranes play a pivotal role in various industries, providing efficient lifting and handling capabilities. Various functions of a crane such as lifting, lowering, extending, retracting, rotating, and stabilizing use hydraulic power provided by a displacement pump of the crane. The displacement pump pumps hydraulic oil to provide the required hydraulic power.

[0003] The use cases of a loader crane are highly variable. An operator may require high speeds at times and precise movements at other times. Since the speed demand for a hydraulic pump is directly linked to the operator's task, the requirements for the hydraulic source also change accordingly. Applying the optimized trade-off among energy efficiency, noise emission, and required performance often presents a contradiction. The same problem arises with other types of lifting equipment equipped with a hydraulic system, such as forklifts or lifting platforms.

[0004] Hence, there may be a demand for improved control of the hydraulic system of lifting equipment.Summary

[0005] This demand is met by an apparatus and a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment, a vehicle, a non-transitory machine-readable medium and a program in accordance with the independent claims. Advantageous embodiments are defined by the dependent claims.

[0006] According to a first aspect, the present disclosure provides an apparatus for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The apparatus comprises processing circuitry configured to receive first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Further, the processing circuitry is configured to receive second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The processing circuitry is configured to determine the target rotational speed based on the target flow rate according to the mode indicated by the user input. Additionally, the processing circuitry is configured to output control data indicating the determined target rotational speed.

[0007] According to a second aspect, the present disclosure provides a vehicle having mounted thereon or being a lifting equipment. The vehicle comprises the apparatus according to the first aspect. Control circuitry on the vehicle is configured to control the rotary drive based on the control data. The hydraulic system comprises at least one of one or more hydraulic cylinders and one or more slewing drives coupled to the displacement pump and drivable by the hydraulic fluid.

[0008] According to a third aspect, the present disclosure provides a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method comprises receiving first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Furthermore, the method comprises receiving second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The method comprises determining the target rotational speed based on the target flow rate according to the mode indicated by the user input. In addition, the method comprises outputting control data indicating the determined target rotational speed.

[0009] According to a fourth aspect, the present disclosure provides a non-transitory machine-readable medium having stored thereon a program having a program code for performing the method according to the third aspect, when the program is executed on a processor or a programmable hardware.

[0010] According to a fifth aspect, the present disclosure provides a program having a program code for performing the method according to the third aspect, when the program is executed on a processor or a programmable hardware.

[0011] The ability to choose from multiple predefined modes allows users to customize the operation of the lifting equipment's hydraulic system based on different requirements or operating conditions. This flexibility can lead to better handling and operation of the lifting equipment and, hence, more efficient and effective performance. By calculating the target rotational speed based on the desired flow rate and the selected mode, the apparatus may optimize the performance of the hydraulic system. This may ensure that the displacement pump operates efficiently, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.Brief description of the Figures

[0012] Some examples of apparatuses and / or methods will be described in the following by way of example only, and with reference to the accompanying figures, in which Fig. 1 illustrates an example of an apparatus for determining a target rotational speed for a rotary drive; Fig. 2 illustrates a graph showing exemplary temporal courses of the target rotational speed determined according to different modes; Fig. 3 illustrates an example of a vehicle; and Fig. 4 illustrates a flowchart of an example of a method for determining a target rotational speed for a rotary drive. Detailed Description

[0013] Some examples are now described in more detail with reference to the enclosed figures. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of the features as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe certain examples should not be restrictive of further possible examples.

[0014] Throughout the description of the figures same or similar reference numerals refer to same or similar elements and / or features, which may be identical or implemented in a modified form while providing the same or a similar function. The thickness of lines, layers and / or areas in the figures may also be exaggerated for clarification.

[0015] When two elements A and B are combined using an "or", this is to be understood as disclosing all possible combinations, i.e. only A, only B as well as A and B, unless expressly defined otherwise in the individual case. As an alternative wording for the same combinations, "at least one of A and B" or "A and / or B" may be used. This applies equivalently to combinations of more than two elements.

[0016] If a singular form, such as "a", "an" and "the" is used and the use of only a single element is not defined as mandatory either explicitly or implicitly, further examples may also use several elements to implement the same function. If a function is described below as implemented using multiple elements, further examples may implement the same function using a single element or a single processing entity. It is further understood that the terms "include", "including", "comprise" and / or "comprising", when used, describe the presence of the specified features, integers, steps, operations, processes, elements, components and / or a group thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components and / or a group thereof.

[0017] Fig. 1 schematically illustrates an apparatus 100 for determining a target rotational speed for a rotary drive (rotary actuator, rotary motion drive) 130 driving a displacement pump 125 of a hydraulic system of a lifting equipment 120.

[0018] The lifting equipment 120 is any machinery (device) for lifting loads (e.g., goods and / or people) using hydraulic power. For example, the lifting equipment may be a crane such as a knuckle boom or loader crane for loading and unloading goods (loads). Alternatively, the lifting equipment may, e.g., be the crane section of a mobile crane (with a vehicle being a mobile platform having mounted thereon the crane section) or the entire mobile crane. In other examples, the lifting equipment may, e.g., be a forklift comprising a pronged device in the front, called forks, which can be inserted under loads to lift and carry them. In still other examples, the lifting equipment may, e.g., be a lifting platform (elevating platform of lift table) comprising a platform supported by a mechanical structure in a liftable manner to a base of the lifting platform.

[0019] The rotary drive 130 is configured to produce (provide) controlled rotational movement. The target rotational speed denotes the desired or intended speed at which the rotary drive 130 should rotate. In other words, the target rotational speed refers to the desired or intended speed of the rotational movement to be provided by the rotary drive 130.

[0020] As schematically indicated in Fig. 1, the displacement pump 125 of the lifting equipment 120 is driven by the rotary drive 130 to provide hydraulic power. For example, the hydraulic power may be provided by means of a flow of hydraulic fluid caused (generated) by the displacement pump 125 when driven by the rotary drive 130. In general, any type of hydraulic fluid suitable for transmitting power efficiently may be used. For example, the hydraulic fluid may be a mineral oil-based hydraulic fluid or a synthetic hydraulic fluid. The hydraulic power provided by the displacement pump 125 is used by one or more consumers of the lifting equipment 120 (not illustrated in Fig. 1). The one or more consumers of the lifting equipment 120 are hydraulically coupled to the displacement pump 125. The displacement pump 125 and the one or more consumers of the crane 120 form the hydraulic system of the lifting equipment 120.

[0021] For example, the one or more consumers may be one or more hydraulic cylinders and / or one or more slewing drives of the lifting equipment 120 for providing various functions of the lifting equipment 120 such as lifting, lowering, extending, tilting, retracting, rotating, and stabilizing. For reasons of simplicity, various elements of the lifting equipment 120 such as its one or more hydraulic cylinders, one or more slewing drives, equipment base (e.g., the crane base of a crane or the base of a lifting platform), lifting devices (e.g., a boom or crane arm of a crane, the forks of a forklift, the platform of a lifting platform) or outriggers (e.g., crane legs) are not illustrated in Fig. 1.

[0022] The rotary drive 130 may be part of the lifting equipment 120. In other examples, the rotary drive 130 may be external to the lifting equipment 120 (e.g., external to a crane such as a loader crane). In other words, the rotary drive 130 is not part of the lifting equipment 120 in some examples. The rotary drive 130 may be any device or system capable of converting energy into mechanical rotation (rotational movement) in a controlled manner. For example, the rotary drive 130 may be an electric rotary drive comprising one or more electric motors for generating the rotational movement. According to examples of the present disclosure, the rotary drive 130 may be an electric rotary drive on a vehicle having mounted thereon (holding, carrying) the lifting equipment 120 or being the lifting equipment 120. Electric rotary drives are also denoted as electric Power Take-Offs (ePTOs). In alternative examples, the rotary drive 130 may be a Power Take-Off (PTO) driven by a drive system 140 (e.g., a combustion engine and optionally a gearbox). According to examples of the present disclosure, the rotary drive 130 may be a PTO of a vehicle having mounted thereon or being the lifting equipment 120. The vehicle may be a land vehicle (e.g., wheeled, tracked or railed) or a watercraft (e.g., a ship, a boat or a barge). For example, the lifting equipment 120 may be mounted to a vehicle such as a truck. For example, the lifting equipment 120 may be a crane (e.g., a knuckle boom or loader crane) mounted to a vehicle such as a truck for loading and unloading goods onto and from the vehicle. The rotary drive 130, in particular when implemented as electric rotary drive, may be detachably attached to the vehicle. In other examples, the rotary drive 130 may be fixedly attached to the vehicle. For reasons of clarity, the vehicle is not shown in Fig. 1.

[0023] The apparatus 100 may be part of the lifting equipment 120 (e.g., be part of a crane). According to examples, equipment control circuitry (equipment controller) 121 for controlling operation of the lifting equipment 120 may comprise the apparatus 100. The equipment control circuitry 121 may, e.g., be coupled to the displacement pump 125 and control operation of the displacement pump 125 and optionally further elements of the lifting equipment 120. In other examples, the apparatus 100 and the equipment control circuitry 121 may be separate elements of the lifting equipment 120. In alternative examples, the apparatus 100 may be external to the lifting equipment 120, i.e., not be part of the lifting equipment 120. For example, a computing cloud communicatively coupled to the lifting equipment 120 (e.g., via a wireless connection) may comprise or be the apparatus 100. In still other examples, the vehicle having mounted thereon the lifting equipment 120 may comprise the apparatus 100. In case the lifting equipment 120 is a crane, the equipment control circuitry 121 may be crane control circuitry (a crane controller) for controlling operation of the crane.

[0024] The apparatus 100 comprises processing circuitry 110. For example, the processing circuitry 110 may be a single dedicated processor, a single shared processor, or a plurality of individual processors, some of which or all of which may be shared, a digital signal processor (DSP) hardware, an application specific integrated circuit (ASIC), a system-on-a-chip (SOC), a neuromorphic processor or a field programmable gate array (FPGA). The processing circuitry 110 may optionally be coupled to, e.g., memory such as read only memory (ROM) for storing software, random access memory (RAM) and / or non-volatile memory. For example, the apparatus 100 may comprise memory configured to store instructions, which when executed by the processing circuitry 110, cause the processing circuitry 110 to perform the steps and methods described herein.

[0025] The processing circuitry 110 is configured to receive first input data 101. The first input data 101 indicate (are encoded with information about) a target flow rate of the hydraulic fluid to be provided (delivered) by the displacement pump 125. The target flow rate denotes the desired, demanded or intended flow rate at which the hydraulic fluid should flow through the hydraulic system of the lifting equipment 120. The hydraulic fluid is to be supplied (pumped) at the target flow rate by the displacement pump 125. For example, the target flow rate may indicate how much volume (e.g., how many liters) of hydraulic fluid the displacement pump 125 should deliver per unit of time (e.g., per second or per minute). The first input data 101 may, e.g., be received from the equipment control circuitry 121. The equipment control circuitry 121 controls the operation of the lifting equipment 120 and is, hence, aware of or able to calculate the required flow rate of hydraulic fluid for the (e.g., intended) operation of the lifting equipment 120. However, the present disclosure is not limited thereto. In other examples, the first input data 101 may be received from another entity (element, circuitry) of the lifting equipment 120. The first input data 101 as well as other input data to the processing circuitry 110 may be real-time data (i.e., data that is delivered / received immediately after collection / generation without significant delay). This may ensure that the target rotational speed can be dynamically adjusted. This real-time feedback loop helps in maintaining optimal performance and safety.

[0026] Further, the processing circuitry 110 is configured to receive second input data 102 indicating a user input. The user input indicates which of a plurality of predefined (operational) modes is to be used for determining the target rotational speed. In other words, the user input specifies a particular mode among several (i.e., two or more) predefined options, and this chosen mode dictates how the target rotational speed is determined. The plurality of predefined modes are different from each other. In particular, the plurality of predefined modes differ from each other in the way the target rotational speed is determined based on the input data received by the processing circuitry 110. For example, the second input data 102 may be received from a remote control (not illustrated in Fig. 1). The remote control is a device for an operator (user) of the lifting equipment 120 for controlling the lifting equipment 120 from a distance. However, the present disclosure is not limited thereto. In other examples, the second input data 102 may be received from another entity such as an element or circuitry of the lifting equipment 120 (e.g., a Human-Machine Interface, HMI, of the lifting equipment 120), a mobile device (e.g., a mobile phone, a laptop-computer or a tablet-computer) of the operator of the lifting equipment 120 or a remote server.

[0027] Additionally, the processing circuitry 110 is configured to determine the target rotational speed for the rotary drive 130 based on the target flow rate according to the mode indicated by the user input. In other words, according to the mode selected by the user, the processing circuitry 110 determines the target rotational speed using the target flow rate indicated by the first input data 101 as input for the determination. The target rotational speed may be constant over time or may vary over time. The way the target rotational speed is determined by the processing circuitry 110 depends on the mode indicated by the user input. For example, a respective computational model may be provided for each of the plurality of modes. Accordingly, the processing circuitry 110 may be configured to determine the target rotational speed using the respective predefined computational model for the mode indicated by the user input. The computational models are mathematical representations (e.g., sets of mathematical equations) for determining the target rotational speed for the rotary drive 130 taking into account the target flow rate indicated by the first input data 101 and optionally further inputs. The computational models may use various signal and / or data processing operations such as signal / data addition, subtraction, multiplication, division, integration, derivation, filtering (e.g., discrete, continuous or both), delaying, etc. to determine the target rotational speed based on the various inputs to the processing circuitry 110.

[0028] The processing circuitry 110 is configured to output control data 103 indicating the determined target rotational speed. The control data 103 are for controlling the rotational speed of the rotary drive 130. The control data 103 may be output by the processing circuitry 110 to various entities - depending on the implementation of the rotary drive 130. For example, the processing circuitry 110 may be configured to output the control data 103 to the rotary drive 130 such that control circuitry of the rotary drive 130 may control the rotary drive 130 to adjust its rotational speed to the determined target rotational speed. In other examples, the processing circuitry 110 may be configured to output the control data 103 to control circuitry for the rotary drive 130 external to the rotary drive 130 such that the external control circuitry may control the rotary drive 130 to adjust its rotational speed to the determined target rotational speed. For example, if the rotary drive is an electric rotary drive on a vehicle having mounted thereon or being the lifting equipment 120, the processing circuitry 110 may be configured to output the control data 103 to the electric rotary drive such that control circuitry of the electric rotary drive may control the electric rotary drive to adjust its rotational speed to the determined target rotational speed. In case the rotary drive 130 is driven by the drive system 140, the processing circuitry 110 may be configured to output the control data 103 to the drive system 140 or control circuitry for the drive system 140 external to the drive system 140 such that the drive system 140 is controlled to adjust the driving of the rotary drive 130 such that the rotational speed of the rotary drive 130 is adjusted to the determined target rotational speed. For example, if the rotary drive 130 is a PTO of a vehicle having mounted thereon or being the lifting equipment 120, the processing circuitry 110 may be configured to output the control data 103 to the vehicle such that vehicle control circuitry of the vehicle may control the drive system 140 of the vehicle (e.g., a combustion engine of the vehicle) based on the control data 103.

[0029] The ability to choose from multiple predefined modes allows the user to customize the operation of the lifting equipment 120's hydraulic system based on different requirements or operating conditions. This flexibility can lead to better handling and operation of the lifting equipment 120 and, hence, more efficient and effective performance. By calculating the target rotational speed based on the target flow rate and the selected mode, the apparatus 100 may optimize the performance of the hydraulic system. This may ensure that the displacement pump operates efficiently, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.

[0030] As described above, the user may select from multiple predefined modes. For example, the plurality of predefined modes may comprise at least a first mode, a second mode and a third mode.

[0031] The first mode is for determining the target rotational speed to optimize power consumption. In other words, this mode is designed to determine the target rotational speed with the primary goal of optimizing power consumption. In this mode, the apparatus 100 calculates the rotational speed in a way that minimizes energy usage, which can lead to lower operational costs and improved energy efficiency. Accordingly, energy emissions may be reduced, leading to improved sustainability. The third mode is for determining the target rotational speed to maximize performance of the lifting equipment 120. In other words, this mode focuses on maximizing the performance of the lifting equipment 120. When this mode is selected, the apparatus 120 determines the rotational speed to achieve high (e.g., the highest possible) performance, likely prioritizing speed and power over energy efficiency. This mode is suitable for scenarios where high levels (e.g., the highest level) of operational performance are desired. The second mode is a trade-off between the first mode and the second mode. In other words, the second mode is a compromise between the first and third modes. It is designed to balance the optimization of power consumption with the need to maximize performance. In this mode, the apparatus 100 calculates a target rotational speed that provides a reasonable trade-off, offering good performance while still being mindful of energy efficiency. This mode is useful in situations where both performance and energy efficiency are important but neither can be fully prioritized over the other. By providing the above modes, the apparatus 100 may be used for a wide range of scenarios, from energy-saving operations to high-performance requirements, making it suitable for various applications and industries. Users can select the mode that best fits their specific needs at any given time, offering a high degree of customization and control over the hydraulic system's operation. This feature improves user satisfaction and adaptability.

[0032] According to examples, the second mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment 120 compared to the third mode. Analogously, the first mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment 120 compared to the second mode. The target rotational speed determined in the second mode provides a performance level that is reduced compared to the third mode. This means that while the second mode offers better performance than the first mode, it does not match the high-performance level of the third mode. The target rotational speed determined in the first mode provides a performance level that is further reduced compared to the second mode. Thus, the first mode offers the lowest performance among the three modes, prioritizing power consumption optimization over performance.

[0033] The first mode is for determining the target rotational speed to provide a reduced power consumption compared to the second mode. Analogously, the second mode is for determining the target rotational speed to provide a reduced power consumption compared to the third mode. The target rotational speed determined in the first mode results in reduced power consumption compared to the second mode. The target rotational speed determined in the second mode results in reduced power consumption compared to the third mode. That is, the first mode is the most energy-efficient, designed to minimize power usage. The second mode strikes a balance, offering better energy efficiency than the high-performance third mode but not as much as the first mode.

[0034] The first to third modes provide a structured approach to balancing performance and energy efficiency. Users can easily understand the trade-offs between different modes, making it easier to select the most appropriate mode for their needs.

[0035] For determining the target rotational speed, the processing circuitry 110 may, e.g., be configured to use a rotational speed offset for increasing the rotational speed of the rotary drive in the second mode and the third mode. A value of the rotational speed offset in the third mode is higher than in the second mode. The processing circuitry 110 uses a rotational speed offset to increase the rotational speed of the rotary drive in both the second mode and the third mode. A value of the rotational speed offset in the third mode is higher than in the second mode. In other words, the offset value in the third mode is higher than in the second mode. This means that the third mode, which focuses on maximizing performance, applies a greater increase in rotational speed compared to the second mode, which balances performance and power consumption.

[0036] The rotational offset may further be used in the first mode. The value of the rotational speed offset in the second mode is higher than in the first mode. The value of the rotational speed offset in the first mode may, e.g., be equal to or less than zero. Accordingly, the first mode, which prioritizes optimizing power consumption, does not increase the rotational speed. In fact, the speed could remain the same or be decreased.

[0037] As is evident from the above, the rotational speed offset refers to a value or adjustment factor that is used to increase or decrease the target rotational speed for the rotary drive 130 by a certain amount. The use of rotational speed offsets provides a method for finely adjusting the target rotational speed. This allows for precise control over the hydraulic system's performance, accommodating different operational requirements. Different offset values for each mode ensure that the apparatus can optimize performance and power consumption based on the selected mode. Higher offsets in the third mode maximize performance, moderate offsets in the second mode balance performance and efficiency, and low offsets in the first mode minimize power consumption.

[0038] For example, for determining the target rotational speed, the processing circuitry 110 may be configured to determine an auxiliary rotational speed for the rotary drive 130 based on the target flow rate, and to determine the target rotational speed by modifying the auxiliary rotational speed based on the rotational speed offset. In other words, the processing circuitry may first calculate an auxiliary rotational speed for the rotary drive 130 based on the target flow rate of hydraulic fluid that is to be provided by the displacement pump 125. For example, the processing circuitry 110 may be configured to determine the auxiliary rotational speed for the rotary drive 130 using the respective computational model for the mode indicated by the second input data 102, wherein the computational model takes the target flow rate as input. After determining the auxiliary rotational speed, the processing circuitry 110 may then modify this speed using the rotational speed offset. The target rotational speed is obtained by applying this offset to the auxiliary rotational speed.

[0039] For example, if the auxiliary rotational speed is, based on the target flow rate indicated by the first input data 101, the mode indicated by the second input data 102 and optionally further inputs, determined to be X revolutions per unit time and the predefined rotational speed offset is Y i revolutions per unit time (with i = 1 ... 3 for the first to third modes and Y 1 < Y 2 < Y 3 , wherein Y 2 , Y 3 > 0 and Y 3 ≤ 0), the resulting target rotational speed is Z = X + Y i revolutions per time unit. In other examples, if an adjustment factor A i (with i = 1 ... 3 for the first to third modes and A 1 < A 2 < A 3 , wherein A 2 , A 3 > 1 and A 1 ≤ 1) is used instead of the set value Y, the resulting target rotational speed is Z = X . A i revolutions per time unit.

[0040] By first determining the auxiliary rotational speed based on the target flow rate, the apparatus 100 may ensure an accurate initial calculation. This helps in achieving a precise control over the hydraulic system's performance. Modifying the auxiliary rotational speed with a rotational speed offset allows for flexible adjustments.

[0041] According to examples, the processing circuitry 110 may be configured to determine the auxiliary rotational speed in the first mode with a reduced dynamic compared to the second mode. Analogously, the processing circuitry 110 may be configured to determine the auxiliary rotational speed in the second mode with a reduced dynamic compared to the third mode. For example, different computational models may be used or parameters of a computational model may be varied between the different modes to provide different dynamics. The dynamic of the auxiliary rotational speed refers to the responsiveness or variability in how the auxiliary rotational speed is calculated based on changes in the target flow rate. In the first mode, the processing circuitry 110 determines the auxiliary rotational speed with a reduced dynamic compared to the second mode. This means that the auxiliary rotational speed changes more slowly or weaker (less distinct) in response to variations in the target flow rate. The first mode prioritizes stability and energy efficiency, leading to smoother and less variable speed adjustments. In the second mode, the processing circuitry 110 determines the auxiliary rotational speed with a reduced dynamic compared to the third mode. This implies that the second mode offers a moderate level of responsiveness, balancing between stability and performance. The speed adjustments are more dynamic than in the first mode but less so than in the third mode. The third mode has the highest dynamic. This mode allows for rapid and strong (distinct) adjustments to the auxiliary rotational speed in response to changes in the target flow rate, prioritizing performance and responsiveness. By varying the dynamic nature of the auxiliary rotational speed calculation, the apparatus 100 may better cater to different operational needs. The first mode's reduced dynamic ensures energy efficiency and stability, while the second and third modes offer progressively higher responsiveness for better performance.

[0042] Summarizing the above, the processing circuitry 110 may be configured to determine the target rotational speed to exhibit a reduced dynamic compared to the target flow rate in the first mode, to exhibit the same dynamic as the target flow rate in the second mode, and to exhibit an increased dynamic compared to the target flow rate in the third mode. In other words, the processing circuitry 110 may determine the target rotational speed's responsiveness (or dynamic) relative to changes in the target flow rate differently across the plurality of modes. In the first mode, the processing circuitry 110 may be configured to determine the target rotational speed with a reduced dynamic compared to the target flow rate. This means that changes in the target flow rate will result in slower or weaker (less distinct) adjustments to the rotational speed, prioritizing stability and energy efficiency. In the second mode, the processing circuitry 110 may determine the target rotational speed with the same dynamic as the target flow rate. Here, the rotational speed changes in direct proportion to changes in the flow rate, offering a balanced approach that mirrors the variability of the flow rate. In the third mode, the processing circuitry 110 may determine the target rotational speed with an increased dynamic compared to the target flow rate. This means that the rotational speed adjustments are more responsive and stronger (more distinct) than the changes in the flow rate, prioritizing maximum performance and quick adaptability.

[0043] The environmentally friendly first mode may, e.g., be used for precise movements or movements with decreased (low) speed. The third mode may, e.g., be used for movements with highest performance. The second mode may be a good compromise for precise and fast movements.

[0044] An exemplary comparison of the target rotational speed determined according to the three different modes described above is illustrated in Fig. 2. The abscissa of graph 200 illustrated in Fig. 2 denotes the time t and the ordinate denotes rotational speed and flow rate.

[0045] The curve 210 represents the temporal course of the target rotational speed determined according to the third mode described above. The curve 220 represents the temporal course of the target rotational speed determined according to second mode described above. The curve 230 represents the temporal course of the target rotational speed determined according to first mode described above. The curves 210, 220 and 230 are determined for the same temporal course 240 of the target flow rate.

[0046] As can be seen from Fig. 2, the determined target rotational speed is highest and most dynamic for the third mode. On the other hand, the determined target rotational speed is lowest and least dynamic for the first mode. The second mode provides a trade-off between the first and the third mode.

[0047] Fig. 3 further illustrates a truck as an exemplary vehicle 300 having mounted thereon (holding) a loader crane (knuckle boom crane) 320 as an exemplary lifting equipment. In the example of Fig. 3, the loader crane 320 comprises hydraulic cylinders 321, 322 and 323 for driving (moving) the crane arm 324 of the loader crane 320. The crane arm 324 is an exemplary lifting device of a lifting equipment. Additionally, the loader crane 320 comprises hydraulic cylinders 325 for driving (moving) the outriggers 326. Further illustrated in Fig. 3 is the slewing drive 328 for rotating the crane arm 324 relative to the base 327 of the loader crane 320. The hydraulic cylinders and the slewing drive(s) are hydraulically coupled to the displacement pump 125 of the loader crane 320 and form the hydraulic system of the loader crane 320. The hydraulic cylinders and the slewing drive(s) are drivable (driven) by the displacement pump 125 of the loader crane 320. The displacement pump 125 of the loader crane 320 is driven by the rotary drive 130 on the vehicle 300.

[0048] The vehicle 300 further comprises the apparatus 100 according to the present disclosure for determining a target rotational speed for the rotary drive 130. As described above, the rotary drive 130 may, e.g., be a PTO of the vehicle 300. For example, the PTO may be driven by a combustion engine and optionally a gearbox of the vehicle 300. In alternative examples, the rotary drive 130 may be an ePTO on the vehicle 300. For reasons of simplicity, the rotary drive 130 is illustrated schematically in Fig. 3.

[0049] Control circuitry 310 on the vehicle 300 is configured to control the rotary drive 130 based on the control data 103 output by the apparatus 100. As described above, the control circuitry 310 may be manifold depending on the type of rotary drive.

[0050] Compared to conventional vehicles, the vehicle 300 may achieve improved control of the loader crane 320's hydraulic system. In particular, the control of the hydraulic system may be adapted to the needs of the loader crane 320's operator. Furthermore, the control of the hydraulic system may be optimized to meet various operator needs such as efficiency and noise emission and, hence, provide improved sustainability.

[0051] Fig. 3 focused on the loader crane 320 as an exemplary lifting equipment. However, as indicated above, present disclosure is not limited to the lifting equipment being the loader crane 320 mounted to the vehicle 300. In general, the lifting equipment may be any type of crane using a displacement pump to provide hydraulic power. Apart from a knuckle boom or loader crane for loading and unloading goods (loads), the lifting equipment may, e.g., be the crane section of a mobile crane (with the vehicle being the mobile platform having mounted thereon the crane section) or the entire mobile crane. It is to be noted further that the present disclosure is not limited to cranes. In other examples, the lifting equipment may, e.g., be a forklift using a displacement pump to provide hydraulic power for various applications such as raising and lowering its forks or tilting the mast of the forklift to which the forks are mounted. In still other examples, the lifting equipment may, e.g., be a lifting platform using a displacement pump to provide hydraulic power for various applications such as raising and lowering its platform.

[0052] For further highlighting the driving of displacement pumps of lifting equipment described above, Fig. 4 illustrates a flowchart of a method 400 for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method 400 comprises receiving 402 first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Furthermore, the method 400 comprises receiving 404 second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The method 400 comprises determining 406 the target rotational speed based on the target flow rate according to the mode indicated by the user input. In addition, the method 400 comprises outputting 408 control data indicating the determined target rotational speed.

[0053] Analogously to what is described above, the method 400 may allow to customize the operation of the lifting equipment's hydraulic system based on different requirements or operating conditions. This flexibility may lead to better handling and operation of the lifting equipment and, hence, more efficient and effective performance. By calculating the target rotational speed based on the target flow rate and the selected mode, the performance of the hydraulic system may be optimized to ensure efficient operation of the displacement pump, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.

[0054] More details and aspects of the method 400 are explained in connection with the proposed technique or one or more examples described above (e.g., Fig. 1 to Fig. 3). The method 400 may comprise one or more additional optional features corresponding to one or more aspects of the proposed technique or one or more examples described above.

[0055] The examples described herein may be summarized as follows: An example (e.g., example 1) relates to an apparatus for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The apparatus comprises processing circuitry configured to receive first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Further, the processing circuitry is configured to receive second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The processing circuitry is configured to determine the target rotational speed based on the target flow rate according to the mode indicated by the user input. Additionally, the processing circuitry is configured to output control data indicating the determined target rotational speed.

[0056] Another example (e.g., example 2) relates to a previous example (e.g., example 1) or to any other example, wherein the plurality of predefined modes comprise at least a first mode, a second mode and a third mode, wherein the first mode is for determining the target rotational speed to optimize power consumption, wherein the third mode is for determining the target rotational speed to maximize performance of the lifting equipment, and wherein the second mode is a trade-off between the first mode and the second mode.

[0057] Another example (e.g., example 3) relates to a previous example (e.g., example 2) or to any other example, wherein the second mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment compared to the third mode, and wherein the first mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment compared to the second mode.

[0058] Another example (e.g., example 4) relates to a previous example (e.g., example 2 or example 3) or to any other example, wherein the first mode is for determining the target rotational speed to provide a reduced power consumption compared to the second mode, and wherein the second mode is for determining the target rotational speed to provide a reduced power consumption compared to the third mode.

[0059] Another example (e.g., example 5) relates to a previous example (e.g., one of the examples 2 to 4) or to any other example, wherein for determining the target rotational speed, the processing circuitry is configured to use a rotational speed offset for increasing the rotational speed of the rotary drive in the second mode and the third mode, wherein a value of the rotational speed offset in the third mode is higher than in the second mode.

[0060] Another example (e.g., example 6) relates to a previous example (e.g., example 5) or to any other example, wherein the value of the rotational speed offset in the second mode is higher than in the first mode.

[0061] Another example (e.g., example 7) relates to a previous example (e.g., one of the examples 5 or 6) or to any other example, wherein, for determining the target rotational speed, the processing circuitry is configured to: determine an auxiliary rotational speed for the rotary drive based on the target flow rate; and determine the target rotational speed by modifying the auxiliary rotational speed based on the rotational speed offset.

[0062] Another example (e.g., example 8) relates to a previous example (e.g., example 7) or to any other example, wherein the processing circuitry is configured to determine the auxiliary rotational speed in the first mode with a reduced dynamic compared to the second mode, and wherein the processing circuitry is configured to determine the auxiliary rotational speed in the second mode with a reduced dynamic compared to the third mode.

[0063] Another example (e.g., example 9) relates to a previous example (e.g., one of the examples 2 to 8) or to any other example, wherein the processing circuitry is configured to determine the target rotational speed to exhibit a reduced dynamic compared to the target flow rate in the first mode, the same dynamic as the target flow rate in the second mode, and an increased dynamic compared to the target flow rate in the third mode.

[0064] Another example (e.g., example 10) relates to a previous example (e.g., one of the examples 1 to 9) or to any other example, wherein the rotary drive is a power take-off of a vehicle, the vehicle having mounted thereon or being the lifting equipment.

[0065] Another example (e.g., example 11) relates to a previous example (e.g., one of the examples 1 to 9) or to any other example, wherein the rotary drive is an electric rotary drive on a vehicle, the vehicle having mounted thereon or being the lifting equipment.

[0066] An example (e.g., example 12) relates to a vehicle having mounted thereon or being a lifting equipment. The vehicle comprises the apparatus according to a previous example (e.g., one of the examples 1 to 11) or to any other example. Control circuitry on the vehicle is configured to control the rotary drive based on the control data. The hydraulic system comprises at least one of one or more hydraulic cylinders and one or more slewing drives coupled to the displacement pump and drivable by the hydraulic fluid.

[0067] Another example (e.g., example 13) relates to a previous example (e.g., example 12) or to any other example, further comprising that the at least one of the one or more hydraulic cylinders and the one or more slewing drives is configured to drive at least one of a lifting device of the lifting equipment and an outrigger of the lifting equipment.

[0068] Another example (e.g., example 14) relates to a previous example (e.g., one of the examples 12 or 13) or to any other example, further comprising that the lifting equipment is a loader crane.

[0069] An example (e.g., example 15) relates to a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method comprises receiving time series data indicating a demanded hydraulic power for operating the lifting equipment. Furthermore, the method comprises determining an average for the demanded hydraulic power based on the time series data. The method additionally comprises determining, based on the average for the demanded hydraulic power, a parameter setting for a computational model for determining the target rotational speed. The method comprises determining the target rotational speed based on the demanded hydraulic power according to the determined parameter setting. In addition, the method comprises outputting control data indicating the determined target rotational speed.

[0070] Another example (e.g., example 16) relates to a non-transitory machine-readable medium having stored thereon a program having a program code for performing the method according to a previous example (e.g., example 15) or to any other example, when the program is executed on a processor or a programmable hardware.

[0071] Another example (e.g., example 17) relates to a program having a program code for performing the method according to a previous example (e.g., example 15) or to any other example, when the program is executed on a processor or a programmable hardware.

[0072] The aspects and features described in relation to a particular one of the previous examples may also be combined with one or more of the further examples to replace an identical or similar feature of that further example or to additionally introduce the features into the further example.

[0073] Examples may further be or relate to a (computer) program including a program code to execute one or more of the above methods when the program is executed on a computer, processor or other programmable hardware component. Thus, steps, operations or processes of different ones of the methods described above may also be executed by programmed computers, processors or other programmable hardware components. Examples may also cover program storage devices, such as digital data storage media, which are machine-, processor- or computer-readable and encode and / or contain machine-executable, processor-executable or computer-executable programs and instructions. Program storage devices may include or be digital storage devices, magnetic storage media such as magnetic disks and magnetic tapes, hard disk drives, or optically readable digital data storage media, for example. Other examples may also include computers, processors, control units, (field) programmable logic arrays ((F)PLAs), (field) programmable gate arrays ((F)PGAs), graphics processor units (GPU), application-specific integrated circuits (ASICs), integrated circuits (ICs) or system-on-a-chip (SoCs) systems programmed to execute the steps of the methods described above.

[0074] It is further understood that the disclosure of several steps, processes, operations or functions disclosed in the description or claims shall not be construed to imply that these operations are necessarily dependent on the order described, unless explicitly stated in the individual case or necessary for technical reasons. Therefore, the previous description does not limit the execution of several steps or functions to a certain order. Furthermore, in further examples, a single step, function, process or operation may include and / or be broken up into several sub-steps, -functions, -processes or -operations.

[0075] If some aspects have been described in relation to a device or system, these aspects should also be understood as a description of the corresponding method. For example, a block, device or functional aspect of the device or system may correspond to a feature, such as a method step, of the corresponding method. Accordingly, aspects described in relation to a method shall also be understood as a description of a corresponding block, a corresponding element, a property or a functional feature of a corresponding device or a corresponding system.

[0076] The following claims are hereby incorporated in the detailed description, wherein each claim may stand on its own as a separate example. It should also be noted that although in the claims a dependent claim refers to a particular combination with one or more other claims, other examples may also include a combination of the dependent claim with the subject matter of any other dependent or independent claim. Such combinations are hereby explicitly proposed, unless it is stated in the individual case that a particular combination is not intended. Furthermore, features of a claim should also be included for any other independent claim, even if that claim is not directly defined as dependent on that other independent claim.

Examples

Embodiment Construction

[0013]Some examples are now described in more detail with reference to the enclosed figures. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of the features as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe certain examples should not be restrictive of further possible examples.

[0014]Throughout the description of the figures same or similar reference numerals refer to same or similar elements and / or features, which may be identical or implemented in a modified form while providing the same or a similar function. The thickness of lines, layers and / or areas in the figures may also be exaggerated for clarification.

[0015]When two elements A and B are combined using an "or", this is to be understood as disclosing all possible combinations, i.e. only A, only B as well as A and B, unless expressly defined otherwise in the individual...

Field

[0001] The present disclosure relates to controlling rotary drives driving displacement pumps of lifting equipment. In particular, examples of the present disclosure relate to an apparatus and a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment, and a vehicle comprising the apparatus.Background

[0002] Cranes, in particular loader cranes play a pivotal role in various industries, providing efficient lifting and handling capabilities. Various functions of a crane such as lifting, lowering, extending, retracting, rotating, and stabilizing use hydraulic power provided by a displacement pump of the crane. The displacement pump pumps hydraulic oil to provide the required hydraulic power.

[0003] The use cases of a loader crane are highly variable. An operator may require high speeds at times and precise movements at other times. Since the speed demand for a hydraulic pump is directly linked to the operator's task, the requirements for the hydraulic source also change accordingly. Applying the optimized trade-off among energy efficiency, noise emission, and required performance often presents a contradiction. The same problem arises with other types of lifting equipment equipped with a hydraulic system, such as forklifts or lifting platforms.

[0004] Hence, there may be a demand for improved control of the hydraulic system of lifting equipment.Summary

[0005] This demand is met by an apparatus and a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment, a vehicle, a non-transitory machine-readable medium and a program in accordance with the independent claims. Advantageous embodiments are defined by the dependent claims.

[0006] According to a first aspect, the present disclosure provides an apparatus for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The apparatus comprises processing circuitry configured to receive first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Further, the processing circuitry is configured to receive second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The processing circuitry is configured to determine the target rotational speed based on the target flow rate according to the mode indicated by the user input. Additionally, the processing circuitry is configured to output control data indicating the determined target rotational speed.

[0007] According to a second aspect, the present disclosure provides a vehicle having mounted thereon or being a lifting equipment. The vehicle comprises the apparatus according to the first aspect. Control circuitry on the vehicle is configured to control the rotary drive based on the control data. The hydraulic system comprises at least one of one or more hydraulic cylinders and one or more slewing drives coupled to the displacement pump and drivable by the hydraulic fluid.

[0008] According to a third aspect, the present disclosure provides a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method comprises receiving first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Furthermore, the method comprises receiving second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The method comprises determining the target rotational speed based on the target flow rate according to the mode indicated by the user input. In addition, the method comprises outputting control data indicating the determined target rotational speed.

[0009] According to a fourth aspect, the present disclosure provides a non-transitory machine-readable medium having stored thereon a program having a program code for performing the method according to the third aspect, when the program is executed on a processor or a programmable hardware.

[0010] According to a fifth aspect, the present disclosure provides a program having a program code for performing the method according to the third aspect, when the program is executed on a processor or a programmable hardware.

[0011] The ability to choose from multiple predefined modes allows users to customize the operation of the lifting equipment's hydraulic system based on different requirements or operating conditions. This flexibility can lead to better handling and operation of the lifting equipment and, hence, more efficient and effective performance. By calculating the target rotational speed based on the desired flow rate and the selected mode, the apparatus may optimize the performance of the hydraulic system. This may ensure that the displacement pump operates efficiently, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.Brief description of the Figures

[0012] Some examples of apparatuses and / or methods will be described in the following by way of example only, and with reference to the accompanying figures, in which Fig. 1 illustrates an example of an apparatus for determining a target rotational speed for a rotary drive; Fig. 2 illustrates a graph showing exemplary temporal courses of the target rotational speed determined according to different modes; Fig. 3 illustrates an example of a vehicle; and Fig. 4 illustrates a flowchart of an example of a method for determining a target rotational speed for a rotary drive. Detailed Description

[0013] Some examples are now described in more detail with reference to the enclosed figures. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of the features as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe certain examples should not be restrictive of further possible examples.

[0014] Throughout the description of the figures same or similar reference numerals refer to same or similar elements and / or features, which may be identical or implemented in a modified form while providing the same or a similar function. The thickness of lines, layers and / or areas in the figures may also be exaggerated for clarification.

[0015] When two elements A and B are combined using an "or", this is to be understood as disclosing all possible combinations, i.e. only A, only B as well as A and B, unless expressly defined otherwise in the individual case. As an alternative wording for the same combinations, "at least one of A and B" or "A and / or B" may be used. This applies equivalently to combinations of more than two elements.

[0016] If a singular form, such as "a", "an" and "the" is used and the use of only a single element is not defined as mandatory either explicitly or implicitly, further examples may also use several elements to implement the same function. If a function is described below as implemented using multiple elements, further examples may implement the same function using a single element or a single processing entity. It is further understood that the terms "include", "including", "comprise" and / or "comprising", when used, describe the presence of the specified features, integers, steps, operations, processes, elements, components and / or a group thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components and / or a group thereof.

[0017] Fig. 1 schematically illustrates an apparatus 100 for determining a target rotational speed for a rotary drive (rotary actuator, rotary motion drive) 130 driving a displacement pump 125 of a hydraulic system of a lifting equipment 120.

[0018] The lifting equipment 120 is any machinery (device) for lifting loads (e.g., goods and / or people) using hydraulic power. For example, the lifting equipment may be a crane such as a knuckle boom or loader crane for loading and unloading goods (loads). Alternatively, the lifting equipment may, e.g., be the crane section of a mobile crane (with a vehicle being a mobile platform having mounted thereon the crane section) or the entire mobile crane. In other examples, the lifting equipment may, e.g., be a forklift comprising a pronged device in the front, called forks, which can be inserted under loads to lift and carry them. In still other examples, the lifting equipment may, e.g., be a lifting platform (elevating platform of lift table) comprising a platform supported by a mechanical structure in a liftable manner to a base of the lifting platform.

[0019] The rotary drive 130 is configured to produce (provide) controlled rotational movement. The target rotational speed denotes the desired or intended speed at which the rotary drive 130 should rotate. In other words, the target rotational speed refers to the desired or intended speed of the rotational movement to be provided by the rotary drive 130.

[0020] As schematically indicated in Fig. 1, the displacement pump 125 of the lifting equipment 120 is driven by the rotary drive 130 to provide hydraulic power. For example, the hydraulic power may be provided by means of a flow of hydraulic fluid caused (generated) by the displacement pump 125 when driven by the rotary drive 130. In general, any type of hydraulic fluid suitable for transmitting power efficiently may be used. For example, the hydraulic fluid may be a mineral oil-based hydraulic fluid or a synthetic hydraulic fluid. The hydraulic power provided by the displacement pump 125 is used by one or more consumers of the lifting equipment 120 (not illustrated in Fig. 1). The one or more consumers of the lifting equipment 120 are hydraulically coupled to the displacement pump 125. The displacement pump 125 and the one or more consumers of the crane 120 form the hydraulic system of the lifting equipment 120.

[0021] For example, the one or more consumers may be one or more hydraulic cylinders and / or one or more slewing drives of the lifting equipment 120 for providing various functions of the lifting equipment 120 such as lifting, lowering, extending, tilting, retracting, rotating, and stabilizing. For reasons of simplicity, various elements of the lifting equipment 120 such as its one or more hydraulic cylinders, one or more slewing drives, equipment base (e.g., the crane base of a crane or the base of a lifting platform), lifting devices (e.g., a boom or crane arm of a crane, the forks of a forklift, the platform of a lifting platform) or outriggers (e.g., crane legs) are not illustrated in Fig. 1.

[0022] The rotary drive 130 may be part of the lifting equipment 120. In other examples, the rotary drive 130 may be external to the lifting equipment 120 (e.g., external to a crane such as a loader crane). In other words, the rotary drive 130 is not part of the lifting equipment 120 in some examples. The rotary drive 130 may be any device or system capable of converting energy into mechanical rotation (rotational movement) in a controlled manner. For example, the rotary drive 130 may be an electric rotary drive comprising one or more electric motors for generating the rotational movement. According to examples of the present disclosure, the rotary drive 130 may be an electric rotary drive on a vehicle having mounted thereon (holding, carrying) the lifting equipment 120 or being the lifting equipment 120. Electric rotary drives are also denoted as electric Power Take-Offs (ePTOs). In alternative examples, the rotary drive 130 may be a Power Take-Off (PTO) driven by a drive system 140 (e.g., a combustion engine and optionally a gearbox). According to examples of the present disclosure, the rotary drive 130 may be a PTO of a vehicle having mounted thereon or being the lifting equipment 120. The vehicle may be a land vehicle (e.g., wheeled, tracked or railed) or a watercraft (e.g., a ship, a boat or a barge). For example, the lifting equipment 120 may be mounted to a vehicle such as a truck. For example, the lifting equipment 120 may be a crane (e.g., a knuckle boom or loader crane) mounted to a vehicle such as a truck for loading and unloading goods onto and from the vehicle. The rotary drive 130, in particular when implemented as electric rotary drive, may be detachably attached to the vehicle. In other examples, the rotary drive 130 may be fixedly attached to the vehicle. For reasons of clarity, the vehicle is not shown in Fig. 1.

[0023] The apparatus 100 may be part of the lifting equipment 120 (e.g., be part of a crane). According to examples, equipment control circuitry (equipment controller) 121 for controlling operation of the lifting equipment 120 may comprise the apparatus 100. The equipment control circuitry 121 may, e.g., be coupled to the displacement pump 125 and control operation of the displacement pump 125 and optionally further elements of the lifting equipment 120. In other examples, the apparatus 100 and the equipment control circuitry 121 may be separate elements of the lifting equipment 120. In alternative examples, the apparatus 100 may be external to the lifting equipment 120, i.e., not be part of the lifting equipment 120. For example, a computing cloud communicatively coupled to the lifting equipment 120 (e.g., via a wireless connection) may comprise or be the apparatus 100. In still other examples, the vehicle having mounted thereon the lifting equipment 120 may comprise the apparatus 100. In case the lifting equipment 120 is a crane, the equipment control circuitry 121 may be crane control circuitry (a crane controller) for controlling operation of the crane.

[0024] The apparatus 100 comprises processing circuitry 110. For example, the processing circuitry 110 may be a single dedicated processor, a single shared processor, or a plurality of individual processors, some of which or all of which may be shared, a digital signal processor (DSP) hardware, an application specific integrated circuit (ASIC), a system-on-a-chip (SOC), a neuromorphic processor or a field programmable gate array (FPGA). The processing circuitry 110 may optionally be coupled to, e.g., memory such as read only memory (ROM) for storing software, random access memory (RAM) and / or non-volatile memory. For example, the apparatus 100 may comprise memory configured to store instructions, which when executed by the processing circuitry 110, cause the processing circuitry 110 to perform the steps and methods described herein.

[0025] The processing circuitry 110 is configured to receive first input data 101. The first input data 101 indicate (are encoded with information about) a target flow rate of the hydraulic fluid to be provided (delivered) by the displacement pump 125. The target flow rate denotes the desired, demanded or intended flow rate at which the hydraulic fluid should flow through the hydraulic system of the lifting equipment 120. The hydraulic fluid is to be supplied (pumped) at the target flow rate by the displacement pump 125. For example, the target flow rate may indicate how much volume (e.g., how many liters) of hydraulic fluid the displacement pump 125 should deliver per unit of time (e.g., per second or per minute). The first input data 101 may, e.g., be received from the equipment control circuitry 121. The equipment control circuitry 121 controls the operation of the lifting equipment 120 and is, hence, aware of or able to calculate the required flow rate of hydraulic fluid for the (e.g., intended) operation of the lifting equipment 120. However, the present disclosure is not limited thereto. In other examples, the first input data 101 may be received from another entity (element, circuitry) of the lifting equipment 120. The first input data 101 as well as other input data to the processing circuitry 110 may be real-time data (i.e., data that is delivered / received immediately after collection / generation without significant delay). This may ensure that the target rotational speed can be dynamically adjusted. This real-time feedback loop helps in maintaining optimal performance and safety.

[0026] Further, the processing circuitry 110 is configured to receive second input data 102 indicating a user input. The user input indicates which of a plurality of predefined (operational) modes is to be used for determining the target rotational speed. In other words, the user input specifies a particular mode among several (i.e., two or more) predefined options, and this chosen mode dictates how the target rotational speed is determined. The plurality of predefined modes are different from each other. In particular, the plurality of predefined modes differ from each other in the way the target rotational speed is determined based on the input data received by the processing circuitry 110. For example, the second input data 102 may be received from a remote control (not illustrated in Fig. 1). The remote control is a device for an operator (user) of the lifting equipment 120 for controlling the lifting equipment 120 from a distance. However, the present disclosure is not limited thereto. In other examples, the second input data 102 may be received from another entity such as an element or circuitry of the lifting equipment 120 (e.g., a Human-Machine Interface, HMI, of the lifting equipment 120), a mobile device (e.g., a mobile phone, a laptop-computer or a tablet-computer) of the operator of the lifting equipment 120 or a remote server.

[0027] Additionally, the processing circuitry 110 is configured to determine the target rotational speed for the rotary drive 130 based on the target flow rate according to the mode indicated by the user input. In other words, according to the mode selected by the user, the processing circuitry 110 determines the target rotational speed using the target flow rate indicated by the first input data 101 as input for the determination. The target rotational speed may be constant over time or may vary over time. The way the target rotational speed is determined by the processing circuitry 110 depends on the mode indicated by the user input. For example, a respective computational model may be provided for each of the plurality of modes. Accordingly, the processing circuitry 110 may be configured to determine the target rotational speed using the respective predefined computational model for the mode indicated by the user input. The computational models are mathematical representations (e.g., sets of mathematical equations) for determining the target rotational speed for the rotary drive 130 taking into account the target flow rate indicated by the first input data 101 and optionally further inputs. The computational models may use various signal and / or data processing operations such as signal / data addition, subtraction, multiplication, division, integration, derivation, filtering (e.g., discrete, continuous or both), delaying, etc. to determine the target rotational speed based on the various inputs to the processing circuitry 110.

[0028] The processing circuitry 110 is configured to output control data 103 indicating the determined target rotational speed. The control data 103 are for controlling the rotational speed of the rotary drive 130. The control data 103 may be output by the processing circuitry 110 to various entities - depending on the implementation of the rotary drive 130. For example, the processing circuitry 110 may be configured to output the control data 103 to the rotary drive 130 such that control circuitry of the rotary drive 130 may control the rotary drive 130 to adjust its rotational speed to the determined target rotational speed. In other examples, the processing circuitry 110 may be configured to output the control data 103 to control circuitry for the rotary drive 130 external to the rotary drive 130 such that the external control circuitry may control the rotary drive 130 to adjust its rotational speed to the determined target rotational speed. For example, if the rotary drive is an electric rotary drive on a vehicle having mounted thereon or being the lifting equipment 120, the processing circuitry 110 may be configured to output the control data 103 to the electric rotary drive such that control circuitry of the electric rotary drive may control the electric rotary drive to adjust its rotational speed to the determined target rotational speed. In case the rotary drive 130 is driven by the drive system 140, the processing circuitry 110 may be configured to output the control data 103 to the drive system 140 or control circuitry for the drive system 140 external to the drive system 140 such that the drive system 140 is controlled to adjust the driving of the rotary drive 130 such that the rotational speed of the rotary drive 130 is adjusted to the determined target rotational speed. For example, if the rotary drive 130 is a PTO of a vehicle having mounted thereon or being the lifting equipment 120, the processing circuitry 110 may be configured to output the control data 103 to the vehicle such that vehicle control circuitry of the vehicle may control the drive system 140 of the vehicle (e.g., a combustion engine of the vehicle) based on the control data 103.

[0029] The ability to choose from multiple predefined modes allows the user to customize the operation of the lifting equipment 120's hydraulic system based on different requirements or operating conditions. This flexibility can lead to better handling and operation of the lifting equipment 120 and, hence, more efficient and effective performance. By calculating the target rotational speed based on the target flow rate and the selected mode, the apparatus 100 may optimize the performance of the hydraulic system. This may ensure that the displacement pump operates efficiently, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.

[0030] As described above, the user may select from multiple predefined modes. For example, the plurality of predefined modes may comprise at least a first mode, a second mode and a third mode.

[0031] The first mode is for determining the target rotational speed to optimize power consumption. In other words, this mode is designed to determine the target rotational speed with the primary goal of optimizing power consumption. In this mode, the apparatus 100 calculates the rotational speed in a way that minimizes energy usage, which can lead to lower operational costs and improved energy efficiency. Accordingly, energy emissions may be reduced, leading to improved sustainability. The third mode is for determining the target rotational speed to maximize performance of the lifting equipment 120. In other words, this mode focuses on maximizing the performance of the lifting equipment 120. When this mode is selected, the apparatus 120 determines the rotational speed to achieve high (e.g., the highest possible) performance, likely prioritizing speed and power over energy efficiency. This mode is suitable for scenarios where high levels (e.g., the highest level) of operational performance are desired. The second mode is a trade-off between the first mode and the second mode. In other words, the second mode is a compromise between the first and third modes. It is designed to balance the optimization of power consumption with the need to maximize performance. In this mode, the apparatus 100 calculates a target rotational speed that provides a reasonable trade-off, offering good performance while still being mindful of energy efficiency. This mode is useful in situations where both performance and energy efficiency are important but neither can be fully prioritized over the other. By providing the above modes, the apparatus 100 may be used for a wide range of scenarios, from energy-saving operations to high-performance requirements, making it suitable for various applications and industries. Users can select the mode that best fits their specific needs at any given time, offering a high degree of customization and control over the hydraulic system's operation. This feature improves user satisfaction and adaptability.

[0032] According to examples, the second mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment 120 compared to the third mode. Analogously, the first mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment 120 compared to the second mode. The target rotational speed determined in the second mode provides a performance level that is reduced compared to the third mode. This means that while the second mode offers better performance than the first mode, it does not match the high-performance level of the third mode. The target rotational speed determined in the first mode provides a performance level that is further reduced compared to the second mode. Thus, the first mode offers the lowest performance among the three modes, prioritizing power consumption optimization over performance.

[0033] The first mode is for determining the target rotational speed to provide a reduced power consumption compared to the second mode. Analogously, the second mode is for determining the target rotational speed to provide a reduced power consumption compared to the third mode. The target rotational speed determined in the first mode results in reduced power consumption compared to the second mode. The target rotational speed determined in the second mode results in reduced power consumption compared to the third mode. That is, the first mode is the most energy-efficient, designed to minimize power usage. The second mode strikes a balance, offering better energy efficiency than the high-performance third mode but not as much as the first mode.

[0034] The first to third modes provide a structured approach to balancing performance and energy efficiency. Users can easily understand the trade-offs between different modes, making it easier to select the most appropriate mode for their needs.

[0035] For determining the target rotational speed, the processing circuitry 110 may, e.g., be configured to use a rotational speed offset for increasing the rotational speed of the rotary drive in the second mode and the third mode. A value of the rotational speed offset in the third mode is higher than in the second mode. The processing circuitry 110 uses a rotational speed offset to increase the rotational speed of the rotary drive in both the second mode and the third mode. A value of the rotational speed offset in the third mode is higher than in the second mode. In other words, the offset value in the third mode is higher than in the second mode. This means that the third mode, which focuses on maximizing performance, applies a greater increase in rotational speed compared to the second mode, which balances performance and power consumption.

[0036] The rotational offset may further be used in the first mode. The value of the rotational speed offset in the second mode is higher than in the first mode. The value of the rotational speed offset in the first mode may, e.g., be equal to or less than zero. Accordingly, the first mode, which prioritizes optimizing power consumption, does not increase the rotational speed. In fact, the speed could remain the same or be decreased.

[0037] As is evident from the above, the rotational speed offset refers to a value or adjustment factor that is used to increase or decrease the target rotational speed for the rotary drive 130 by a certain amount. The use of rotational speed offsets provides a method for finely adjusting the target rotational speed. This allows for precise control over the hydraulic system's performance, accommodating different operational requirements. Different offset values for each mode ensure that the apparatus can optimize performance and power consumption based on the selected mode. Higher offsets in the third mode maximize performance, moderate offsets in the second mode balance performance and efficiency, and low offsets in the first mode minimize power consumption.

[0038] For example, for determining the target rotational speed, the processing circuitry 110 may be configured to determine an auxiliary rotational speed for the rotary drive 130 based on the target flow rate, and to determine the target rotational speed by modifying the auxiliary rotational speed based on the rotational speed offset. In other words, the processing circuitry may first calculate an auxiliary rotational speed for the rotary drive 130 based on the target flow rate of hydraulic fluid that is to be provided by the displacement pump 125. For example, the processing circuitry 110 may be configured to determine the auxiliary rotational speed for the rotary drive 130 using the respective computational model for the mode indicated by the second input data 102, wherein the computational model takes the target flow rate as input. After determining the auxiliary rotational speed, the processing circuitry 110 may then modify this speed using the rotational speed offset. The target rotational speed is obtained by applying this offset to the auxiliary rotational speed.

[0039] For example, if the auxiliary rotational speed is, based on the target flow rate indicated by the first input data 101, the mode indicated by the second input data 102 and optionally further inputs, determined to be X revolutions per unit time and the predefined rotational speed offset is Y i revolutions per unit time (with i = 1 ... 3 for the first to third modes and Y 1 < Y 2 < Y 3 , wherein Y 2 , Y 3 > 0 and Y 3 ≤ 0), the resulting target rotational speed is Z = X + Y i revolutions per time unit. In other examples, if an adjustment factor A i (with i = 1 ... 3 for the first to third modes and A 1 < A 2 < A 3 , wherein A 2 , A 3 > 1 and A 1 ≤ 1) is used instead of the set value Y, the resulting target rotational speed is Z = X . A i revolutions per time unit.

[0040] By first determining the auxiliary rotational speed based on the target flow rate, the apparatus 100 may ensure an accurate initial calculation. This helps in achieving a precise control over the hydraulic system's performance. Modifying the auxiliary rotational speed with a rotational speed offset allows for flexible adjustments.

[0041] According to examples, the processing circuitry 110 may be configured to determine the auxiliary rotational speed in the first mode with a reduced dynamic compared to the second mode. Analogously, the processing circuitry 110 may be configured to determine the auxiliary rotational speed in the second mode with a reduced dynamic compared to the third mode. For example, different computational models may be used or parameters of a computational model may be varied between the different modes to provide different dynamics. The dynamic of the auxiliary rotational speed refers to the responsiveness or variability in how the auxiliary rotational speed is calculated based on changes in the target flow rate. In the first mode, the processing circuitry 110 determines the auxiliary rotational speed with a reduced dynamic compared to the second mode. This means that the auxiliary rotational speed changes more slowly or weaker (less distinct) in response to variations in the target flow rate. The first mode prioritizes stability and energy efficiency, leading to smoother and less variable speed adjustments. In the second mode, the processing circuitry 110 determines the auxiliary rotational speed with a reduced dynamic compared to the third mode. This implies that the second mode offers a moderate level of responsiveness, balancing between stability and performance. The speed adjustments are more dynamic than in the first mode but less so than in the third mode. The third mode has the highest dynamic. This mode allows for rapid and strong (distinct) adjustments to the auxiliary rotational speed in response to changes in the target flow rate, prioritizing performance and responsiveness. By varying the dynamic nature of the auxiliary rotational speed calculation, the apparatus 100 may better cater to different operational needs. The first mode's reduced dynamic ensures energy efficiency and stability, while the second and third modes offer progressively higher responsiveness for better performance.

[0042] Summarizing the above, the processing circuitry 110 may be configured to determine the target rotational speed to exhibit a reduced dynamic compared to the target flow rate in the first mode, to exhibit the same dynamic as the target flow rate in the second mode, and to exhibit an increased dynamic compared to the target flow rate in the third mode. In other words, the processing circuitry 110 may determine the target rotational speed's responsiveness (or dynamic) relative to changes in the target flow rate differently across the plurality of modes. In the first mode, the processing circuitry 110 may be configured to determine the target rotational speed with a reduced dynamic compared to the target flow rate. This means that changes in the target flow rate will result in slower or weaker (less distinct) adjustments to the rotational speed, prioritizing stability and energy efficiency. In the second mode, the processing circuitry 110 may determine the target rotational speed with the same dynamic as the target flow rate. Here, the rotational speed changes in direct proportion to changes in the flow rate, offering a balanced approach that mirrors the variability of the flow rate. In the third mode, the processing circuitry 110 may determine the target rotational speed with an increased dynamic compared to the target flow rate. This means that the rotational speed adjustments are more responsive and stronger (more distinct) than the changes in the flow rate, prioritizing maximum performance and quick adaptability.

[0043] The environmentally friendly first mode may, e.g., be used for precise movements or movements with decreased (low) speed. The third mode may, e.g., be used for movements with highest performance. The second mode may be a good compromise for precise and fast movements.

[0044] An exemplary comparison of the target rotational speed determined according to the three different modes described above is illustrated in Fig. 2. The abscissa of graph 200 illustrated in Fig. 2 denotes the time t and the ordinate denotes rotational speed and flow rate.

[0045] The curve 210 represents the temporal course of the target rotational speed determined according to the third mode described above. The curve 220 represents the temporal course of the target rotational speed determined according to second mode described above. The curve 230 represents the temporal course of the target rotational speed determined according to first mode described above. The curves 210, 220 and 230 are determined for the same temporal course 240 of the target flow rate.

[0046] As can be seen from Fig. 2, the determined target rotational speed is highest and most dynamic for the third mode. On the other hand, the determined target rotational speed is lowest and least dynamic for the first mode. The second mode provides a trade-off between the first and the third mode.

[0047] Fig. 3 further illustrates a truck as an exemplary vehicle 300 having mounted thereon (holding) a loader crane (knuckle boom crane) 320 as an exemplary lifting equipment. In the example of Fig. 3, the loader crane 320 comprises hydraulic cylinders 321, 322 and 323 for driving (moving) the crane arm 324 of the loader crane 320. The crane arm 324 is an exemplary lifting device of a lifting equipment. Additionally, the loader crane 320 comprises hydraulic cylinders 325 for driving (moving) the outriggers 326. Further illustrated in Fig. 3 is the slewing drive 328 for rotating the crane arm 324 relative to the base 327 of the loader crane 320. The hydraulic cylinders and the slewing drive(s) are hydraulically coupled to the displacement pump 125 of the loader crane 320 and form the hydraulic system of the loader crane 320. The hydraulic cylinders and the slewing drive(s) are drivable (driven) by the displacement pump 125 of the loader crane 320. The displacement pump 125 of the loader crane 320 is driven by the rotary drive 130 on the vehicle 300.

[0048] The vehicle 300 further comprises the apparatus 100 according to the present disclosure for determining a target rotational speed for the rotary drive 130. As described above, the rotary drive 130 may, e.g., be a PTO of the vehicle 300. For example, the PTO may be driven by a combustion engine and optionally a gearbox of the vehicle 300. In alternative examples, the rotary drive 130 may be an ePTO on the vehicle 300. For reasons of simplicity, the rotary drive 130 is illustrated schematically in Fig. 3.

[0049] Control circuitry 310 on the vehicle 300 is configured to control the rotary drive 130 based on the control data 103 output by the apparatus 100. As described above, the control circuitry 310 may be manifold depending on the type of rotary drive.

[0050] Compared to conventional vehicles, the vehicle 300 may achieve improved control of the loader crane 320's hydraulic system. In particular, the control of the hydraulic system may be adapted to the needs of the loader crane 320's operator. Furthermore, the control of the hydraulic system may be optimized to meet various operator needs such as efficiency and noise emission and, hence, provide improved sustainability.

[0051] Fig. 3 focused on the loader crane 320 as an exemplary lifting equipment. However, as indicated above, present disclosure is not limited to the lifting equipment being the loader crane 320 mounted to the vehicle 300. In general, the lifting equipment may be any type of crane using a displacement pump to provide hydraulic power. Apart from a knuckle boom or loader crane for loading and unloading goods (loads), the lifting equipment may, e.g., be the crane section of a mobile crane (with the vehicle being the mobile platform having mounted thereon the crane section) or the entire mobile crane. It is to be noted further that the present disclosure is not limited to cranes. In other examples, the lifting equipment may, e.g., be a forklift using a displacement pump to provide hydraulic power for various applications such as raising and lowering its forks or tilting the mast of the forklift to which the forks are mounted. In still other examples, the lifting equipment may, e.g., be a lifting platform using a displacement pump to provide hydraulic power for various applications such as raising and lowering its platform.

[0052] For further highlighting the driving of displacement pumps of lifting equipment described above, Fig. 4 illustrates a flowchart of a method 400 for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method 400 comprises receiving 402 first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Furthermore, the method 400 comprises receiving 404 second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The method 400 comprises determining 406 the target rotational speed based on the target flow rate according to the mode indicated by the user input. In addition, the method 400 comprises outputting 408 control data indicating the determined target rotational speed.

[0053] Analogously to what is described above, the method 400 may allow to customize the operation of the lifting equipment's hydraulic system based on different requirements or operating conditions. This flexibility may lead to better handling and operation of the lifting equipment and, hence, more efficient and effective performance. By calculating the target rotational speed based on the target flow rate and the selected mode, the performance of the hydraulic system may be optimized to ensure efficient operation of the displacement pump, reducing energy consumption and wear on the components and, hence, leading to cost savings and a lower environmental impact.

[0054] More details and aspects of the method 400 are explained in connection with the proposed technique or one or more examples described above (e.g., Fig. 1 to Fig. 3). The method 400 may comprise one or more additional optional features corresponding to one or more aspects of the proposed technique or one or more examples described above.

[0055] The examples described herein may be summarized as follows: An example (e.g., example 1) relates to an apparatus for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The apparatus comprises processing circuitry configured to receive first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump. Further, the processing circuitry is configured to receive second input data indicating a user input. The user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed. The processing circuitry is configured to determine the target rotational speed based on the target flow rate according to the mode indicated by the user input. Additionally, the processing circuitry is configured to output control data indicating the determined target rotational speed.

[0056] Another example (e.g., example 2) relates to a previous example (e.g., example 1) or to any other example, wherein the plurality of predefined modes comprise at least a first mode, a second mode and a third mode, wherein the first mode is for determining the target rotational speed to optimize power consumption, wherein the third mode is for determining the target rotational speed to maximize performance of the lifting equipment, and wherein the second mode is a trade-off between the first mode and the second mode.

[0057] Another example (e.g., example 3) relates to a previous example (e.g., example 2) or to any other example, wherein the second mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment compared to the third mode, and wherein the first mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment compared to the second mode.

[0058] Another example (e.g., example 4) relates to a previous example (e.g., example 2 or example 3) or to any other example, wherein the first mode is for determining the target rotational speed to provide a reduced power consumption compared to the second mode, and wherein the second mode is for determining the target rotational speed to provide a reduced power consumption compared to the third mode.

[0059] Another example (e.g., example 5) relates to a previous example (e.g., one of the examples 2 to 4) or to any other example, wherein for determining the target rotational speed, the processing circuitry is configured to use a rotational speed offset for increasing the rotational speed of the rotary drive in the second mode and the third mode, wherein a value of the rotational speed offset in the third mode is higher than in the second mode.

[0060] Another example (e.g., example 6) relates to a previous example (e.g., example 5) or to any other example, wherein the value of the rotational speed offset in the second mode is higher than in the first mode.

[0061] Another example (e.g., example 7) relates to a previous example (e.g., one of the examples 5 or 6) or to any other example, wherein, for determining the target rotational speed, the processing circuitry is configured to: determine an auxiliary rotational speed for the rotary drive based on the target flow rate; and determine the target rotational speed by modifying the auxiliary rotational speed based on the rotational speed offset.

[0062] Another example (e.g., example 8) relates to a previous example (e.g., example 7) or to any other example, wherein the processing circuitry is configured to determine the auxiliary rotational speed in the first mode with a reduced dynamic compared to the second mode, and wherein the processing circuitry is configured to determine the auxiliary rotational speed in the second mode with a reduced dynamic compared to the third mode.

[0063] Another example (e.g., example 9) relates to a previous example (e.g., one of the examples 2 to 8) or to any other example, wherein the processing circuitry is configured to determine the target rotational speed to exhibit a reduced dynamic compared to the target flow rate in the first mode, the same dynamic as the target flow rate in the second mode, and an increased dynamic compared to the target flow rate in the third mode.

[0064] Another example (e.g., example 10) relates to a previous example (e.g., one of the examples 1 to 9) or to any other example, wherein the rotary drive is a power take-off of a vehicle, the vehicle having mounted thereon or being the lifting equipment.

[0065] Another example (e.g., example 11) relates to a previous example (e.g., one of the examples 1 to 9) or to any other example, wherein the rotary drive is an electric rotary drive on a vehicle, the vehicle having mounted thereon or being the lifting equipment.

[0066] An example (e.g., example 12) relates to a vehicle having mounted thereon or being a lifting equipment. The vehicle comprises the apparatus according to a previous example (e.g., one of the examples 1 to 11) or to any other example. Control circuitry on the vehicle is configured to control the rotary drive based on the control data. The hydraulic system comprises at least one of one or more hydraulic cylinders and one or more slewing drives coupled to the displacement pump and drivable by the hydraulic fluid.

[0067] Another example (e.g., example 13) relates to a previous example (e.g., example 12) or to any other example, further comprising that the at least one of the one or more hydraulic cylinders and the one or more slewing drives is configured to drive at least one of a lifting device of the lifting equipment and an outrigger of the lifting equipment.

[0068] Another example (e.g., example 14) relates to a previous example (e.g., one of the examples 12 or 13) or to any other example, further comprising that the lifting equipment is a loader crane.

[0069] An example (e.g., example 15) relates to a method for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment. The method comprises receiving time series data indicating a demanded hydraulic power for operating the lifting equipment. Furthermore, the method comprises determining an average for the demanded hydraulic power based on the time series data. The method additionally comprises determining, based on the average for the demanded hydraulic power, a parameter setting for a computational model for determining the target rotational speed. The method comprises determining the target rotational speed based on the demanded hydraulic power according to the determined parameter setting. In addition, the method comprises outputting control data indicating the determined target rotational speed.

[0070] Another example (e.g., example 16) relates to a non-transitory machine-readable medium having stored thereon a program having a program code for performing the method according to a previous example (e.g., example 15) or to any other example, when the program is executed on a processor or a programmable hardware.

[0071] Another example (e.g., example 17) relates to a program having a program code for performing the method according to a previous example (e.g., example 15) or to any other example, when the program is executed on a processor or a programmable hardware.

[0072] The aspects and features described in relation to a particular one of the previous examples may also be combined with one or more of the further examples to replace an identical or similar feature of that further example or to additionally introduce the features into the further example.

[0073] Examples may further be or relate to a (computer) program including a program code to execute one or more of the above methods when the program is executed on a computer, processor or other programmable hardware component. Thus, steps, operations or processes of different ones of the methods described above may also be executed by programmed computers, processors or other programmable hardware components. Examples may also cover program storage devices, such as digital data storage media, which are machine-, processor- or computer-readable and encode and / or contain machine-executable, processor-executable or computer-executable programs and instructions. Program storage devices may include or be digital storage devices, magnetic storage media such as magnetic disks and magnetic tapes, hard disk drives, or optically readable digital data storage media, for example. Other examples may also include computers, processors, control units, (field) programmable logic arrays ((F)PLAs), (field) programmable gate arrays ((F)PGAs), graphics processor units (GPU), application-specific integrated circuits (ASICs), integrated circuits (ICs) or system-on-a-chip (SoCs) systems programmed to execute the steps of the methods described above.

[0074] It is further understood that the disclosure of several steps, processes, operations or functions disclosed in the description or claims shall not be construed to imply that these operations are necessarily dependent on the order described, unless explicitly stated in the individual case or necessary for technical reasons. Therefore, the previous description does not limit the execution of several steps or functions to a certain order. Furthermore, in further examples, a single step, function, process or operation may include and / or be broken up into several sub-steps, -functions, -processes or -operations.

[0075] If some aspects have been described in relation to a device or system, these aspects should also be understood as a description of the corresponding method. For example, a block, device or functional aspect of the device or system may correspond to a feature, such as a method step, of the corresponding method. Accordingly, aspects described in relation to a method shall also be understood as a description of a corresponding block, a corresponding element, a property or a functional feature of a corresponding device or a corresponding system.

[0076] The following claims are hereby incorporated in the detailed description, wherein each claim may stand on its own as a separate example. It should also be noted that although in the claims a dependent claim refers to a particular combination with one or more other claims, other examples may also include a combination of the dependent claim with the subject matter of any other dependent or independent claim. Such combinations are hereby explicitly proposed, unless it is stated in the individual case that a particular combination is not intended. Furthermore, features of a claim should also be included for any other independent claim, even if that claim is not directly defined as dependent on that other independent claim.

Examples

Embodiment Construction

[0013]Some examples are now described in more detail with reference to the enclosed figures. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of the features as well as equivalents and alternatives to the features. Furthermore, the terminology used herein to describe certain examples should not be restrictive of further possible examples.

[0014]Throughout the description of the figures same or similar reference numerals refer to same or similar elements and / or features, which may be identical or implemented in a modified form while providing the same or a similar function. The thickness of lines, layers and / or areas in the figures may also be exaggerated for clarification.

[0015]When two elements A and B are combined using an "or", this is to be understood as disclosing all possible combinations, i.e. only A, only B as well as A and B, unless expressly defined otherwise in the individual...

Claims

1. An apparatus (100) for determining a target rotational speed for a rotary drive (130) driving a displacement pump (125) of a hydraulic system of a lifting equipment (120), the apparatus (100) comprising processing circuitry (110) configured to: receive first input data (101) indicating a target flow rate of hydraulic fluid to be provided by the displacement pump (125); receive second input data (102) indicating a user input, wherein the user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed; determine the target rotational speed based on the target flow rate according to the mode indicated by the user input; and output control data (103) indicating the determined target rotational speed.

2. The apparatus (100) of claim 1, wherein the plurality of predefined modes comprise at least a first mode, a second mode and a third mode, wherein the first mode is for determining the target rotational speed to optimize power consumption, wherein the third mode is for determining the target rotational speed to maximize performance of the lifting equipment (120), and wherein the second mode is a trade-off between the first mode and the second mode.

3. The apparatus (100) of claim 2, wherein the second mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment (120) compared to the third mode, and wherein the first mode is for determining the target rotational speed to provide a reduced performance of the lifting equipment (120) compared to the second mode.

4. The apparatus (100) of claim 2 or claim 3, wherein the first mode is for determining the target rotational speed to provide a reduced power consumption compared to the second mode, and wherein the second mode is for determining the target rotational speed to provide a reduced power consumption compared to the third mode.

5. The apparatus (100) of any one of claims 2 to 4, wherein, for determining the target rotational speed, the processing circuitry (110) is configured to use a rotational speed offset for increasing the rotational speed of the rotary drive (130) in the second mode and the third mode, wherein a value of the rotational speed offset in the third mode is higher than in the second mode.

6. The apparatus (100) of claim 5, wherein the value of the rotational speed offset in the second mode is higher than in the first mode.

7. The apparatus (100) of claim 5 or claim 6, wherein, for determining the target rotational speed, the processing circuitry (110) is configured to: determine an auxiliary rotational speed for the rotary drive (130) based on the target flow rate; and determine the target rotational speed by modifying the auxiliary rotational speed based on the rotational speed offset.

8. The apparatus (100) of claim 7, wherein the processing circuitry (110) is configured to determine the auxiliary rotational speed in the first mode with a reduced dynamic compared to the second mode, and wherein the processing circuitry (110) is configured to determine the auxiliary rotational speed in the second mode with a reduced dynamic compared to the third mode.

9. The apparatus (100) of any one of claims 2 to 8, wherein the processing circuitry (110) is configured to determine the target rotational speed to exhibit: a reduced dynamic compared to the target flow rate in the first mode; the same dynamic as the target flow rate in the second mode; and an increased dynamic compared to the target flow rate in the third mode.

10. The apparatus (100) of any one of claims 1 to 9, wherein the rotary drive (130) is a power take-off of a vehicle, the vehicle having mounted thereon or being the lifting equipment (120).

11. The apparatus (100) of any one of claims 1 to 9, wherein the rotary drive (130) is an electric rotary drive on a vehicle, the vehicle having mounted thereon or being the lifting equipment (120).

12. A vehicle (300) having mounted thereon or being a lifting equipment (320), wherein the vehicle (300) comprises the apparatus (100) according to any one of claims 1 to 11, wherein control circuitry (410) on the vehicle (300) is configured to control the rotary drive (130) based on the control data (103), and wherein the hydraulic system comprises at least one of one or more hydraulic cylinders (321, 322, 323, 325) and one or more slewing drives (328) coupled to the displacement pump (125) and drivable by the hydraulic fluid.

13. The vehicle (300) of claim 12, wherein the at least one of the one or more hydraulic cylinders (321, 322, 323, 325) and the one or more slewing drives (328) is configured to drive at least one of a lifting device (424) of the lifting equipment (320) and an outrigger (426) of the lifting equipment (320).

14. The vehicle (300) of claim 12 or claim 13, wherein the lifting equipment (320) is a loader crane.

15. A method (400) for determining a target rotational speed for a rotary drive driving a displacement pump of a hydraulic system of a lifting equipment, the method (400) comprising: receiving (402) first input data indicating a target flow rate of hydraulic fluid to be provided by the displacement pump; receiving (404) second input data indicating a user input, wherein the user input indicates which of a plurality of predefined modes is to be used for determining the target rotational speed; determining (406) the target rotational speed based on the target flow rate according to the mode indicated by the user input; and outputting (408) control data indicating the determined target rotational speed.

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