ATTACHMENT

Description

[0001] The invention relates to an attachment according to the preamble of claim 1 and to a method for operating an attachment according to the preamble of claim 14. EP 1 344 443 A1 discloses such an attachment according to the preamble of claim 1. Furthermore, a mulcher for use with a carrier vehicle, for example a tractor, is already known from the prior art. This mulcher has a hydraulic motor with a maximum and a minimum displacement and is drivable via a hydraulic supply of the carrier vehicle. The maximum displacement and the minimum displacement are manually set following installation of the mulcher on the carrier vehicle and before commissioning of the carrier vehicle and mulcher, and are unchangeable during use of the mulcher. A suboptimal setting of the minimum and / or maximum displacement can result in a reduction in the performance of the mulcher.Furthermore, for each change to the minimum and / or maximum displacement, the operating state of the mulcher and carrier vehicle must be interrupted and the minimum and / or maximum displacement must be manually adjusted by qualified personnel. To do this, a shredding rotor of the mulcher must be brought to a standstill each time and then started again and brought up to a nominal speed. If the mulcher is braked by material to be shredded during operation, the input pressure of the carrier vehicle increases. If a threshold pressure is exceeded by the input pressure, the displacement of the hydraulic motor is hydraulically changed and increases from the minimum displacement to the maximum displacement. This reduces the speed of the mulcher and increases the torque provided by the mulcher's hydraulic motor to ensure effective shredding of the material.

[0002] The object of the invention is, in particular, to provide a generic device with improved properties regarding simpler and / or faster commissioning. This object is achieved according to the invention by the features of patent claims 1 and 14, while advantageous embodiments and further developments of the invention can be found in the subclaims.

[0003] The invention relates to an attachment, in particular a milling machine and / or a mulcher, for use with a carrier vehicle, with at least one functional unit which is provided for energy supply by the carrier vehicle.

[0004] It is proposed that the attachment comprise at least one control unit, in particular a control and / or regulating unit, which automatically controls and / or regulates at least one limit value of an operating parameter of the functional unit in at least one operating state. This advantageously enables simple and / or rapid commissioning to be achieved. Advantageously, manual processes and / or the need for specialist personnel to set and / or regulate the limit value can be eliminated, which in particular allows costs to be saved. Particularly advantageously, changing and / or commissioning of the attachment and / or carrier vehicle can be carried out quickly and easily. Furthermore, the attachment can be operated with optimal settings to achieve performance optimization.

[0005] An "attachment" is understood in particular to mean a device that is intended to provide at least one predefined function by means of its functional unit and that can be mounted on a carrier vehicle, in particular on various carrier vehicles, in particular of different types. The attachment can, for example, be any construction and / or agricultural and / or preferably forestry attachment that appears appropriate to a person skilled in the art, in particular a pair of pliers and / or a grapple and / or a ram and / or a saw and / or a mower and / or preferably a milling machine, in particular an asphalt milling machine and / or a stump cutter and / or a digger and / or a snow blower and / or a mulcher. A "functional unit" is understood in particular to mean a unit that performs the predefined function of the attachment.The functional unit can, for example, comprise at least one saw blade and / or a milling tool and / or a cutting tool and / or a rotor, in particular a comminution rotor, and / or a gripping arm and / or a battering ram and / or a pair of pliers.

[0006] A "carrier vehicle" is understood, in particular, to be a vehicle designed to be equipped with at least one attachment for performing a function of the attachment. In particular, the attachment can be pulled, pushed, carried, raised, lowered, and / or pivoted by a carrier vehicle. The carrier vehicle preferably has at least one bearing unit designed to support the attachment on the carrier vehicle. In an assembled state, the bearing unit advantageously forms at least one common positive connection with at least one corresponding bearing means of the attachment. The carrier vehicle can, in particular, be a landscaping vehicle, a snow removal vehicle, an agricultural vehicle, a construction vehicle, and / or another vehicle suitable for use with the attachment.Preferably, the carrier vehicle is a tractor and / or a crawler vehicle and / or an excavator and / or a wheel loader and / or a skid steer loader.

[0007] The fact that the functional unit is "provided for a power supply by the carrier vehicle" should be understood in particular to mean that the functional unit requires at least one type of energy, which the carrier vehicle provides in the operating state, to perform its function. In particular, the energy can comprise electrical, mechanical and / or hydraulic energy. In particular, the carrier vehicle has a supply unit for supplying the attachment with energy, specifically a mechanical, hydraulic, pneumatic and / or electrical energy supply unit. The carrier vehicle advantageously has at least one connecting unit, which is provided for transmitting energy from the carrier vehicle to the functional unit. The connecting unit can in particular comprise at least one electrical line and / or preferably at least one hose.For example, the attachment, in particular the functional unit, can have at least one hydraulic motor which can be driven via a hydraulic supply unit of the carrier vehicle.

[0008] A "hydraulic motor" is understood, in particular, to be a unit that, in at least one operating state, converts at least one hydraulic energy into at least one mechanical energy. In particular, the hydraulic motor has at least one transmission unit for converting the hydraulic energy into mechanical energy. Advantageously, the attachment has at least one energy transmission unit designed to transmit the mechanical energy to another unit of the functional unit. For example, the energy transmission unit could have at least one traction drive, for example, a belt drive, and / or a piston drive and / or a gear drive.Advantageously, the supply unit of the carrier vehicle has at least one hydraulic pump for supplying the hydraulic motor with hydraulic energy, which can be driven, for example, electrically and / or preferably by means of an internal combustion engine of the carrier vehicle.

[0009] A "limit value of an operating parameter" is understood to mean, in particular, a predefined value of the operating parameter that cannot be further reduced and / or increased in the operating state and / or based on which the control unit initiates at least one predefined process if the value is exceeded and / or undershot. In particular, the limit value can comprise a maximum, a minimum, and / or a threshold value.

[0010] An "automatically" performed process is understood to mean, in particular, a process that runs independently during its execution, in particular without any operator intervention. In particular, the operator can perform at least one manual start action to activate the automatic process. Advantageously, the operator can perform a stop action to interrupt and / or halt the automatic process.

[0011] "Intended" should be understood in particular to mean specifically programmed, designed, and / or equipped. The fact that an object is intended for a specific function should be understood in particular to mean that the object fulfills and / or performs this specific function in at least one application and / or operating state.

[0012] It is further proposed that the control unit electrically controls and / or regulates the limit value of the operating parameter of the functional unit and / or the operating parameter of the functional unit in the operating state. Advantageously, the control unit comprises at least one algorithm according to which the control unit controls and / or regulates the limit value of the operating parameter in the operating state. Advantageously, the algorithm determines an optimal limit value of the parameter and / or an optimal instantaneous value of the operating parameter, in particular to maximize the performance of the functional unit. This makes it possible, in particular, to dispense with mechanical control and / or regulation of the limit value. Advantageously, the accuracy and / or speed of the control and / or regulation of the limit value and / or the operating parameter can be improved.This is particularly advantageous in ensuring that maximum power can always be provided to the attachment. Furthermore, additional processes such as setting a threshold pressure, above which the control unit controls and / or regulates the limit value of the operating parameter, can be eliminated, allowing immediate response to any changes in the input pressure and / or speed.

[0013] It is further proposed that the control unit, in the operating state, controls and / or regulates the limit value of the operating parameter of the functional unit to a setpoint. A "setpoint" is to be understood, in particular, as a value that is defined as a desired value. Advantageously, the control unit controls and / or regulates a current value in the event of a deviation from the setpoint to the setpoint. In particular, the setpoint is defined by at least one operating parameter. Advantageously, the control unit automatically detects the setpoint. Preferably, the setpoint is defined by at least one input pressure of the carrier vehicle and / or at least one speed of at least one unit of the attachment. Particularly preferably, the setpoint serves to optimize the performance of the functional unit. It is conceivable that an operator could set the setpoint. Advantageously, however, the setpoint is set automatically by the control unit.This allows for particularly high performance of the functional unit. Advantageously, if at least one operating parameter changes, the setpoint can be automatically adjusted to the changed operating parameter.

[0014] Furthermore, it is proposed that the control unit, in the operating state, controls and / or regulates a further operating parameter of the functional unit by controlling and / or regulating the limit value of the operating parameter of the functional unit. In particular, the further operating parameter can be a power, a pressure and / or a speed of the attachment. Advantageously, the setpoint value of the limit of the operating parameter is defined by at least one further setpoint value of the further operating parameter. Preferably, the further setpoint value of the further operating parameter is embodied as a predefined nominal speed of the attachment. For example, the nominal speed could be defined during manufacture of the attachment. Particularly preferably, the setpoint value of the limit value is defined as a value of the operating parameter at which the attachment has the nominal speed.In this way, in particular, control and / or regulation of the further operating parameter can be provided in a simple manner.

[0015] It is also proposed that the attachment have at least one sensor unit, in particular a sensor unit assigned to a functional unit, for detecting at least one value of at least one operating parameter, in particular the further operating parameter, of the functional unit, wherein the sensor unit, in the operating state, provides this value to the control unit for processing. For example, the value of the operating parameter can comprise a rotational speed of the attachment. Advantageously, the attachment has at least one transmission unit for transmitting the detected value from the sensor unit to the control unit. The transmission unit can, for example, have a cable and / or a data bus and / or an antenna and / or a radio transmitter and / or a radio transmitter.In this context, "processing" is understood to mean, in particular, a process in which the control unit compares the value with at least one target value and / or at least one further value of another operating parameter and, in particular, initiates at least one further process, such as increasing and / or decreasing the value, based on the comparison. This can, in particular, simplify the control and / or regulation of the limit value. The detected value can advantageously contribute to determining the target value of the limit value. Furthermore, external sensor units for detecting the value can be dispensed with.

[0016] It is further proposed that the attachment have at least one sensor unit, in particular a sensor unit assigned to the carrier vehicle, for detecting at least one value of at least one operating parameter of the carrier vehicle, wherein the sensor unit, in the operating state, provides this value to the control unit for processing. For example, the value of the operating parameter can comprise an inlet pressure of the carrier vehicle. Advantageously, the attachment has at least one transmission unit for transmitting the detected value from the sensor unit to the control unit. The transmission unit can, for example, have a cable and / or a data bus and / or an antenna and / or a radio transmitter and / or a radio transmitter. This can, in particular, simplify the control and / or regulation of the limit value.When changing the carrier vehicle, the attachment can be easily and quickly adjusted to a new carrier vehicle.

[0017] In particular, the attachment can have a sensor unit which comprises the sensor unit assigned to the functional unit and the sensor unit assigned to the carrier vehicle, whereby a construction can be advantageously simplified.

[0018] The sensor unit, in particular the sensor unit assigned to the functional unit and / or the sensor unit assigned to the carrier vehicle, advantageously has at least one speed detection unit. The speed detection unit advantageously has at least one light barrier and / or at least one acceleration sensor and / or at least one vibration sensor and / or at least one microphone. Analogous to common tachometers used in vehicles, the sensor unit preferably has at least one Hall sensor. This makes it possible, in particular, to detect the speed of the attachment and to define the target value of the limit value. Advantageously, external sensor units for detecting the speed of the attachment can be dispensed with.

[0019] It is further proposed that the sensor unit, in particular the sensor unit assigned to the functional unit and / or the sensor unit assigned to the carrier vehicle, has at least one pressure detection unit. The pressure detection unit advantageously has at least one piezoelectric sensor and / or a strain gauge and / or a wound spring element analogous to conventional Bourdon tube pressure gauges. The pressure detection unit preferably has at least one damping fluid, in particular for damping vibrations. The damping fluid can in particular comprise at least one oil. This makes it possible, in particular, to detect the inlet pressure of the carrier vehicle and to define the target value of the limit value. External sensor units for detecting the inlet pressure of the carrier vehicle can advantageously be dispensed with.

[0020] The functional unit advantageously comprises at least one axial piston variable displacement motor. An "axial piston variable displacement motor" is understood in particular to mean a hydraulic motor designed to transmit mechanical energy converted from hydraulic energy through at least one torque and having a variable displacement volume. A "displacement volume" is understood in particular to mean a volume of hydraulic fluid that the axial piston variable displacement motor moves in a single revolution. A "hydraulic fluid" is understood in particular to mean a fluid designed to absorb hydraulic energy and release it to convert the hydraulic energy into mechanical energy. The hydraulic fluid preferably has a viscosity that allows it to be pumped. In particular, the hydraulic fluid comprises at least one oil.In particular, the displacement volume, with a constant hydraulic fluid quantity supplied by the carrier vehicle, is inversely proportional to the speed of the axial piston variable displacement motor and, in particular, proportional to the torque of the axial piston variable displacement motor. The axial piston variable displacement motor advantageously has a minimum displacement volume and at least a maximum displacement volume. This can, in particular, improve the performance of the functional unit, particularly compared to attachments that have hydraulic motors with a fixed displacement volume. Advantageously, the displacement volume can be changed depending on the load on the attachment in order to achieve a torque of the functional unit that is adapted to the load.

[0021] The limit value of the operating parameter of the functional unit is advantageously designed as a minimum or maximum displacement volume of the axial piston variable displacement motor. In particular, the minimum displacement volume is a displacement volume at which, in a load-free state of the attachment, the rotor has the predefined nominal speed. In particular, the maximum displacement volume is defined by a maximum hydraulic fluid capacity of the attachment. When the attachment is put into operation, the control unit preferably controls and / or regulates a displacement volume of the attachment from the maximum displacement volume to the minimum displacement volume. Particularly preferably, the control unit determines a value of the minimum displacement volume based on at least one piece of information determined by the sensor unit. For example, the information could include the rotational speed of the attachment. In particular, the rotational speed is inversely proportional to the displacement volume.Preferably, the control unit monitors the rotational speed of the attachment during control and / or regulation of the displacement volume from the maximum displacement volume to the minimum displacement volume. Particularly preferably, the control unit stops the control and / or regulation of the displacement volume when the rotational speed reaches the predefined nominal speed and controls and / or regulates the minimum displacement volume to the currently set displacement volume. In an alternative embodiment, the algorithm could use the value of the minimum displacement volume when the attachment is first put into operation, the information from the sensor unit and the nominal speed to determine the minimum displacement volume. In particular, the control unit controls and / or regulates the minimum displacement volume to the value.Advantageously, the control unit monitors the value in the operating state and, if the value changes to a new value in the operating state, controls and / or regulates the minimum displacement to the new value. This allows, in particular, high performance of the axial piston variable displacement motor to be achieved, particularly compared to axial piston variable displacement motors without automatic control and / or regulation of the minimum and / or maximum displacement. Advantageously, the control and / or regulation of the minimum and / or maximum displacement can be carried out in all operating states of the attachment.

[0022] In a further embodiment of the invention, it is proposed that the functional unit comprises at least one electric motor, and the limit value of the operating parameter is an electrical limit value. An "electric motor" is to be understood, in particular, as a unit that converts at least one electrical energy into at least one mechanical energy in at least one operating state. In particular, the electric motor comprises at least one rotor and at least one stator. The operating parameter can be embodied, for example, as an electrical current, in particular an effective current and / or a peak current, an electrical voltage, in particular an effective voltage and / or a peak voltage, and / or an electrical power. This makes it possible, in particular, to achieve a high degree of robustness of the functional unit. Moving components such as hydraulic fluid and / or pistons and / or gears could advantageously be omitted.This can be particularly advantageous in achieving flexibility of the functional unit. In particular, a minimal delay between a setting action and a setting de can be achieved.

[0023] The functional unit preferably comprises at least one comminution unit, in particular a comminution rotor. A "comminution unit", in particular a "comminution rotor", is to be understood in particular as a unit which is intended to comminute at least one material, in particular into pieces smaller than 10 cm³, advantageously smaller than 8 cm³, particularly advantageously smaller than 6 cm³, preferably smaller than 4 cm³, and particularly preferably smaller than 2 cm³. The material could, for example, comprise snow and / or earth; preferably, the material comprises at least one plant material, such as grass and / or wood. The comminution unit commins the material in particular by applying a mechanical force, preferably a torque.For example, the comminution unit could have at least one rotor on which at least one cutting tool for comminution of material is arranged. In particular, the rotor could have a main direction of extent that is aligned parallel to a direction of gravity in at least one operating state. Preferably, the rotor has a main direction of extent that is aligned perpendicular to a direction of gravity in the operating state. This makes it possible, in particular, to achieve simple comminution of material. Advantageously, changing and / or commissioning the attachment for comminution of material can be carried out quickly and easily.

[0024] The invention further relates to a method for operating an attachment with at least one functional unit which is supplied with energy by a carrier vehicle.

[0025] It is proposed that at least one limit value of an operating parameter of the functional unit be automatically controlled and / or regulated, which advantageously allows for simple and / or rapid commissioning. Advantageously, manual processes and / or the need for specialist personnel to set and / or regulate the limit value can be eliminated, which in particular allows for cost savings. Particularly advantageously, changing and / or commissioning the attachment and / or carrier vehicle can be carried out quickly and easily. Furthermore, the attachment can be operated with optimal settings to achieve performance optimization.

[0026] Further advantages will become apparent from the following description of the drawings. The drawings illustrate two exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will also expediently consider the features individually and combine them into useful further combinations.

[0027] They show: Fig. 1 shows a system with a carrier vehicle and an attachment in a schematic representation, Fig. 2 shows a part of the attachment in a more detailed, schematic representation, Fig. 3 shows a schematic flow diagram of a method for operating the attachment and Fig. 4 shows a part of another attachment in a more detailed schematic representation.

[0028] Fig. 1shows a system 34a with a carrier vehicle 10 and an attachment 12a. The carrier vehicle 10 is designed as a tracked vehicle. Alternatively, however, the carrier vehicle 10 could also be designed as any vehicle deemed appropriate by a person skilled in the art, for example as a tractor, an excavator, a skid steer loader, or a wheel loader. The attachment 12a is arranged on the carrier vehicle 10. The attachment 12a is designed as a mulcher. Alternatively, the attachment 12a could also be designed as a tiller, in particular a snow blower, stump cutter, or tree cutter. The attachment 12a is intended for use with a plurality of carrier vehicles, in particular a plurality of types of carrier vehicles, and in particular also with the carrier vehicle 10. The carrier vehicle 10 has a bearing unit 62. In an assembled state, the bearing unit 62 cooperates with corresponding bearing means (not shown) of the attachment 12a.The corresponding storage means of the attachment 12a can cooperate with further storage units (not shown) of a variety of types of carrier vehicles.

[0029] Part of the attachment 12a is in Fig. 2 shown in more detail. The attachment 12a has a functional unit 14a. The functional unit 14a has a shredding unit 32a. The shredding unit 32a has a rotor 54a. The shredding unit 32a has a plurality of cutting tools 38a. The cutting tools 38a are arranged on the rotor 54a. The cutting tools 38a are identical to one another, which is why only one of the cutting tools 38a is provided with a reference symbol in the figures.

[0030] The functional unit 14a has an axial piston variable displacement motor 28a for driving the rotor 54a. The axial piston variable displacement motor 28a converts hydraulic energy into mechanical energy. The axial piston variable displacement motor 28a has a rotor unit (not shown). The rotor unit is arranged within an interior space (not shown) of the axial piston variable displacement motor 28a. The interior space serves to accommodate hydraulic fluid, which transfers the hydraulic energy to the rotor unit. The mechanical energy generates a torque of the rotor unit. The axial piston variable displacement motor 28a transfers the torque to the rotor 54a via an energy transmission unit 40a, in particular a belt drive.

[0031] The functional unit 14a is provided for energy supply by the carrier vehicle 10. The carrier vehicle 10 has a supply unit 36a. The supply unit 36a is provided for supplying the functional unit 14a with energy. The supply unit 36a has a hydraulic pump. The hydraulic pump could be designed as an electrically driven hydraulic pump. Alternatively, the supply unit 36a could have a combustion-driven hydraulic pump. The carrier vehicle 10 has a connection unit 46a. The connection unit 46a is provided for providing energy transmission from the hydraulic pump to the attachment 12a. The connection unit 46a has a plurality of hoses 56a. The hoses 56a are identical to one another, which is why only one of the hoses 56a is given a reference numeral in the figures. The hoses 56a provide a discharge and a supply of hydraulic fluid.The flow direction of the hydraulic fluid within the hoses 56a is shown by arrows.

[0032] The attachment 12a has an adjustment unit 44a. The adjustment unit 44a is used to set a minimum displacement volume of the axial piston variable displacement motor 28a. The adjustment unit 44a is used to set a maximum displacement volume of the axial piston variable displacement motor 28a. The adjustment unit 44a has a solenoid valve for changing the minimum and / or maximum displacement volume. When the solenoid valve opens and closes, the volume of the interior of the axial piston variable displacement motor 28a decreases or increases. The attachment 12a has a passage unit 58a. The passage unit 58a is used to adjust a displacement volume of the axial piston variable displacement motor 28a. The passage unit 58a can, for example, have another solenoid valve and / or a magnetic flap. The adjustment unit 44a and the passage unit 58a each have a motor unit (not shown). The motor units can, for example, have electromagnets.The electromagnets provide opening and closing of the solenoid valves and / or the solenoid flap.

[0033] The attachment 12a has a control unit 16a. The control unit 16a controls at least one limit value of an operating parameter of the functional unit 14a in at least one operating state. The control unit 16a automatically controls the limit value in the operating state. The operating parameter is configured as a displacement volume of the attachment 12a. The limit value is configured as the minimum displacement volume. The control unit 16a automatically controls another limit value in the operating state. The further limit value is configured as the maximum displacement volume.

[0034] The control unit 16a electrically controls the limit value and the further limit value of the operating parameter of the functional unit 14a. The control unit 16a electrically regulates the operating parameter of the functional unit 14a. The control unit 16a is connected to the second adjustment unit 44a via a transmission unit 52a. The transmission unit 52a is designed as a data line. The additional transmission units mentioned below are identical to the transmission unit 52a, which is why a detailed description of the additional transmission units is omitted.

[0035] The attachment 12a has a sensor unit 20a assigned to a functional unit. The sensor unit 20a is used to detect a value of a rotational speed of the rotor 54a. The sensor unit 20a provides the value to the control unit 16a for processing. The sensor unit 20a is connected to the control unit 16a via a further transmission unit 52a. The sensor unit 20a has a rotational speed detection unit 24a. The rotational speed detection unit 24a has a light barrier. Alternatively and / or additionally, the rotational speed detection unit 24a could have a microphone and / or a vibration sensor and / or an acceleration sensor. The sensor unit 20a is arranged in a close range of the rotor 54a. The sensor unit 20a measures the rotational speed of the rotor 54a.Alternatively, the sensor unit 20a could be arranged in close proximity to the energy transmission unit 40a and measure a further rotational speed of the axial piston variable speed motor 28a to determine the rotational speed of the rotor 54a. Alternatively, the sensor unit 20a could be configured integrally with the axial piston variable speed motor 28a.

[0036] The attachment 12a has an additional sensor unit 22a assigned to the carrier vehicle. The additional sensor unit 22a serves to detect a value of an input pressure of the carrier vehicle 10. The additional sensor unit 22a provides the value to the control unit 16a for processing. The additional sensor unit 22a is connected to the control unit 16a via an additional transmission unit 52a. The additional sensor unit 22a has a pressure detection unit 26a. The pressure detection unit 26a has a piezoelectric pressure sensor. Alternatively and / or additionally, the pressure detection unit 26a could have a wound spring element and / or a strain gauge. The additional sensor unit 22a is arranged in the vicinity of the connection unit 46a.

[0037] The control unit 16a controls the limit value and the further limit value of the operating parameter of the functional unit 14a to a setpoint and a further setpoint. The setpoint and the further setpoint are defined by the speed of the rotor 54a and the inlet pressure of the carrier vehicle 10. The setpoint is designed as a minimum displacement volume, which generates a predefined nominal speed of the rotor 54a when the attachment 12a is unloaded. The further setpoint is designed as a maximum displacement volume, exceeding which would damage the axial piston variable displacement motor 28a. The control unit 16a has an algorithm that determines the setpoint and the further setpoint using the speed and the inlet pressure of the carrier vehicle 10.

[0038] The control unit 16a controls a further operating parameter of the functional unit 14a by controlling the limit value of the operating parameter of the functional unit 14a. The further operating parameter is configured as a power of the functional unit 14a. The further operating parameter depends on the operating parameter, the speed, and the inlet pressure. The algorithm determines a maximum value of the further operating parameter using the speed, the inlet pressure, and the operating parameter. The control unit 16 regulates the operating parameter to a value that maximizes the further operating parameter.

[0039] In Fig. 3A schematic flow diagram of a method for operating the attachment 12a is shown. In an activation step 100a, the carrier vehicle 10 and the attachment 12a are transferred to the operating state. In a measuring step 110a, the further sensor unit 22a determines a value of the inlet pressure of the carrier vehicle 10. The further sensor unit 22a transmits the value to the control unit 16a via the transmission unit 52a. The control unit 16a determines the further target value of the maximum displacement volume using the value of the inlet pressure. The control unit 16a has a memory unit (not shown). The memory unit is designed as a common electronic storage medium. The control unit 16a stores the further target value of the maximum displacement volume in the memory unit.

[0040] The measuring step 110a follows the activation step 100a. After the measuring step 110a and during the operation of the attachment 12a, the additional sensor unit 22a continues to determine the value of the inlet pressure and transmits it to the control unit 16a. In an adjusting step 120a, the control unit 16a controls the adjusting unit 44a. The control unit 16a opens or closes the solenoid valve of the adjusting unit 44a by controlling the electromagnet of the adjusting unit 44a. The control unit 16a automatically controls the maximum displacement volume to the additional setpoint. The adjusting step 120a follows the measuring step 110a. The control unit 16a monitors the maximum displacement volume after the adjusting step 120a. If the value of the inlet pressure changes, the control unit 16a determines a new additional setpoint using the new value of the inlet pressure and repeats the adjusting step 120a.

[0041] In a further measuring step 130a, the displacement of the axial piston variable displacement motor 28a is continuously reduced from the maximum displacement. The control unit 16a automatically controls the passage unit 58a to regulate the displacement. The control unit 16a closes the solenoid valve and / or the solenoid flap of the passage unit 58a by controlling the motor unit of the passage unit 58a. While the displacement is reduced, the speed of the rotor 54a increases. The first sensor unit 20a determines a value of the speed of the rotor 54a while the displacement is reduced. The first sensor unit 20a transmits the value to the control unit 16a via the transmission unit 52a. The control unit 16a automatically monitors the value. When the value reaches a predefined nominal speed, the control unit 16a stops reducing the displacement. The value is configured as the setpoint for the minimum displacement.The control unit 16a stores the setpoint value of the minimum displacement volume in the storage unit. If the minimum displacement volume and / or the maximum displacement volume change, for example due to use of the attachment 12a with another carrier vehicle (not shown) that is different from the carrier vehicle 10, the control unit 16a can use the stored setpoint value and / or further setpoint value when remounting the attachment 12a to the carrier vehicle 10. The measuring steps 110a, 130a are omitted in this case. The further measuring step 130a follows the setting step 120a. After the further measuring step 130a and during operation of the attachment 12a, the sensor unit 20a continues to determine the value of the rotational speed and transmits it to the control unit 16a. In a further setting step 140a, the control unit 16a controls the adjustment unit 44a.The control unit 16a opens or closes the solenoid valve of the adjustment unit 44a by controlling the electromagnet of the adjustment unit 44a. The control unit 16a automatically controls the minimum displacement of the axial piston variable displacement motor 28a to the current displacement. The further adjustment step 140a follows the measuring step 110a or the activation step 100a in the case of an already existing setpoint. The control unit 16a monitors the minimum displacement after the further adjustment step 140a. If the value of the input pressure changes, the control unit 16a determines a new setpoint using the new value of the input pressure and repeats the further adjustment step 140a.

[0042] In a control step 150a, the control unit 16a determines an optimal value for the displacement volume using the value of the rotational speed of the rotor 54a and the value of the inlet pressure of the host vehicle 10. The value of the inlet pressure of the host vehicle 10 is determined by the further sensor unit 22a and transmitted to the control unit 16a by the transmission unit 52a. The optimal value is a value of the displacement volume at which the performance of the functional unit 14a is maximum. The control unit 16a regulates the displacement volume to the optimal value. The control unit 16a opens or closes the solenoid valve and / or the magnetic flap of the passage unit 58a by controlling the electromagnet of the passage unit 58a. The control unit 16a regulates the performance of the functional unit 14a to a maximum value. The control unit 16a monitors the displacement volume after the control step 150a.If the values transmitted by the sensor units 20a, 22a change, the control unit 16a repeats the control step 150a. The control step 150a follows the further control step 140a.In . Fig. 4 A further embodiment of the invention is shown. The following descriptions and the drawings are essentially limited to the differences between the embodiments, whereby with regard to identically designated method steps and identical components, in particular with regard to method steps and / or components with the same reference numerals, reference is also made to the drawings and / or the description of the other embodiments, in particular to the Fig. 1 to 3 To distinguish the embodiments, the letter a is added to the reference numerals of the embodiment in the Figures 1 to 3 In the example of the Fig. 4the letter a is replaced by the letter b.

[0043] Fig. 4shows part of a further attachment 12b. The further attachment 12b is intended for use with a variety of carrier vehicles, in particular a variety of types of carrier vehicles, and in particular also with the carrier vehicle 10. The further attachment 12b has an electric motor 30b instead of the axial piston variable displacement motor 28a. The electric motor 30b has a magnetic rotor 50b. The electric motor 30b has a stator 48b. A further control unit 16b controls an electrical limit value of an operating parameter of the further attachment 12b. The operating parameter is embodied as an electrical current. Alternatively, the operating parameter could be embodied as an electrical voltage and / or an electrical power. The electrical limit value is embodied as a maximum current supplied to a functional unit 14b. The electrical limit value has a threshold value.Exceeding the threshold may result in damage to the electric motor 30b. The electrical limit value depends in particular on the voltage provided by a supply unit 36b and on the maximum current provided by the supply unit 36b.

[0044] A connection unit 46b is designed as an electrical line. A sensor unit 22b has a current detection unit 18b. The current detection unit 18b has a voltage sensor. The voltage sensor measures a voltage from the connection unit 46b. The current detection unit 18b has a current sensor. The current sensor is connected between the connection unit 46b and the electric motor 30b. The further sensor unit 22b determines the maximum current provided by the supply unit 36b. The further sensor unit 22b determines the voltage provided by the further supply unit 36b. The control unit 16b is connected to the electric motor 30b via the transmission unit 52b. The control unit 16b has a pulse width modulation function.The control unit 16b determines a target value for the pulse width using the maximum current provided by the supply unit 36b, the voltage provided by the supply unit 36b, and the threshold value. The control unit 16b controls the pulse width to the target value. Reference symbol

[0045] 10Carrier vehicle 12Attachment 14Functional unit 16Control unit 18Current detection unit 20Sensor unit 22Sensor unit 24Speed detection unit 26Pressure detection unit 28Axial piston variable displacement motor 30Electric motor 32Crushing unit 34System 36Supply unit 38Cutting tool 40Energy transfer unit 44Adjustment unit 46Connection unit 48Stator 50Magnetic rotor 52Transmission unit 54Rotor 56Hose 58Pass-through unit 62Bearing unit 100Activation step 110Measurement step 120Setting step 130Measurement step 140Setting step 150Control step

Claims

1. An attachment device (12a-b), in particular milling machine and / or mulcher, for use with a carrier vehicle (10), with at least one functional unit (14a-b) which is configured for a supply of energy by way of the carrier vehicle (10), and with at least one control unit (16a-b), characterized in that the control unit is configured to automatically control and / or regulate, in at least one operating state, at least one limit value of an operating parameter of the functional unit (14a-b).

2. The attachment device (12a-b) according to claim 1, characterized in that the control unit (16a-b) is configured to electrically control and / or regulate the limit value of the operating parameter of the functional unit (14a-b) and / or the operating parameter of the functional unit (14a-b) in the operating state.

3. The attachment device (12a-b) according to claim 1 or 2, characterized in that the control unit (16a-b) is configured to control and / or regulate, in the operating state, the limit value of the operating parameter of the functional unit (14a-b) to a setpoint value.

4. The attachment device (12a-b) according to claim 3, characterized in that the control unit (16a-b) is configured to control and / or regulate, in the operating state, a further operating parameter of the functional unit (14a-b) by a control and / or regulation of the limit value of the operating parameter of the functional unit (14a-b).

5. The attachment device (12a-b) according to any one of the preceding claims, characterized by at least one sensor unit (20a-b) for detection of at least one value of at least one operating parameter of the functional unit (14a-b), wherein the sensor unit (20a-b) is configured to provide, in the operating state, said value to the control unit (16a-b) for processing.

6. The attachment device (12a-b) according to any one of the preceding claims, characterized by at least one sensor unit (22a-b) for detection of at least one value of at least one operating parameter of the carrier vehicle (10), wherein the sensor unit (22a-b) is configured to provide, in the operating state, said value to the control unit (16a-b) for processing.

7. The attachment device (12a-b) according to claim 5 or 6, characterized in that the sensor unit (20a-b) has a rotational speed detection unit (24a-b).

8. The attachment device (12a) according to any one of claims 5 to 7, characterized in that the sensor unit (22a) has a pressure detection unit (26a).

9. The attachment device (12a) according to any one of the preceding claims, characterized in that the functional unit (14a) has at least one axial piston adjustment motor (28a).

10. The attachment device (12a) according to claim 9, characterized in that the limit value of the operating parameter of the functional unit (14a) is a minimum or maximum displacement volume of the axial piston adjustment motor (28a).

11. The attachment device (12b) according to any one of claims 1 to 8, characterized in that the functional unit (14b) has at least one electric motor (30b), and the limit value of the operating parameter of the functional unit (14b) is an electric limit value.

12. The attachment device (12a-b) according to any one of the preceding claims, characterized in that the functional unit (14a-b) has at least one comminution unit (32a-b).

13. A system (34a) with at least one attachment device (12a-b) according to any one of the preceding claims and with the carrier vehicle (10).

14. A method for operating an attachment device (12a-b), in particular according to any one of claims 1 to 12, with at least one functional unit (14a-b) which is supplied with energy by a carrier vehicle (10), characterized in that at least one limit value of an operating parameter of the functional unit (14a-b) is controlled and / or regulated automatically.