Electrical processing device with intermediate circuit electronics

Abstract

The invention relates to an electric machining device (10) with a housing (14), an output mechanism (38) for a tool (32) for machining a workpiece, an electric motor (12) for driving the output mechanism (38), and an intermediate circuit electronics (42) for generating a rectified intermediate circuit voltage (U). IC ) from a supply voltage (U S ) of the processing device (10) and a power electronics unit (38) for controlling the electric motor (12) by means of a voltage derived from the intermediate circuit voltage (U IC ) generated motor voltage signal (U M ), wherein the power electronics (38), the DC link electronics (42) and the electric motor (12) form a drive train (44) which is housed in the casing (14) together with at least part of the output mechanism (28). It is proposed that a converter circuit (48) be connected upstream of the DC link electronics (42), which is derived from the supply voltage (U S) a dynamically adjustable setpoint of the DC link voltage (U IC ) provides.

Description

[0001] The invention relates to an electric machining device comprising a housing, an output mechanism for a tool for machining a workpiece, and an electric motor for driving the output mechanism. According to the preamble of independent claim 1, intermediate circuit electronics for generating a rectified intermediate circuit voltage from a supply voltage of the machining device and power electronics for controlling the electric motor by means of a motor voltage signal generated from the intermediate circuit voltage are further provided, wherein the power electronics, the intermediate circuit electronics, and the electric motor form a drive train which is integrated with at least a part of the output mechanism in the housing of the machining device. State of the art

[0002] Battery-powered power tools, especially handheld power tools, have increasingly replaced their mains-powered counterparts in recent years, primarily due to the lighter and more powerful versions of interchangeable battery packs and electric motors. Among electric motors, electrically commutated (EC) and brushless direct current (BLDC) motors have become particularly established. An EC motor is a multi-phase synchronous motor controlled by an inverter bridge circuit (e.g., an H6 bridge in a three-phase EC motor) within a power electronics unit. Such a bridge circuit typically consists of numerous semiconductor switches (e.g., MOSFETs, IGBTs, bipolar power transistors, etc.) that use an applied DC voltage to perform electronic commutation for the individual phases of the EC motor via pulse-width modulation (PWM).Due to the high switching frequency of the semiconductor switches (typically in the kHz range), the applied DC voltage is usually capacitively filtered by one or more capacitors connected in parallel. This filtered or smoothed voltage is also referred to as the intermediate circuit voltage.

[0003] It is known to increase the performance and / or operating time of electrical processing tools by means of various types of converter circuits for power supply. For example, for a battery-powered processing tool, an AC / DC converter can be used as an internal solution according to EP 2535149 A2, or as an external adapter connectable to an electromechanical interface for a replaceable battery pack, which converts the mains voltage into a rectified intermediate circuit voltage, according to EP 4297934 A1. Likewise, it is possible to convert the supply voltage, which is available as DC voltage from another DC voltage source (e.g., an external battery network or backpack), into a corresponding intermediate circuit voltage using an internal or external DC / DC converter. An internal step-up DC / DC converter is known, for example, from EP 2991807 A1, while EP 3070028 A1 discloses a DC / DC converter in the replaceable battery pack.For mains-powered processing equipment with a particularly high power requirement, it is also known to provide an internal power factor correction circuit (PFC) which increases the supply voltage to a higher intermediate circuit voltage, for example to achieve sinusoidal commutation.

[0004] With a constant DC link voltage, the power electronics can only adjust the operating point (speed and / or torque) of the EC motor to a limited extent using PWM, as the switching time of the semiconductor switches prevents the duty cycle from being reduced arbitrarily. Furthermore, a significantly reduced duty cycle has a detrimental effect on the drive train, since efficiency is highest at a duty cycle of 100% and decreases accordingly at reduced duty cycles. This increases losses in the power electronics and the EC motor, leading to higher heat generation and a shorter operating time. In addition, wired and / or electromagnetic interference (EMI) is typically lowest at 100% PWM and increases with a reduced duty cycle.Therefore, if the cycle time is too reduced, operation may no longer comply with standards, or stronger filtering may be necessary. Stronger filtering generally results in higher costs, a larger footprint, and increased weight of the electrical processing device.

[0005] The object of the invention is to provide an electrical processing device that, compared to the prior art, ensures operation with higher energy efficiency in conjunction with the lowest possible interference radiation. Advantages of the invention

[0006] To solve this problem, a converter circuit is connected upstream of the DC link electronics. This converter circuit provides a dynamically adjustable target value for the DC link voltage from the supply voltage. This allows for particularly advantageous optimized operation of the electrical processing device by increasing the voltage range in which the device can be operated, thus eliminating the dependence of the processing device's performance on deviations from the ideal voltage.

[0007] In the context of the invention, electrical processing equipment includes, among other things, machine tools that can be powered by mains voltage, battery voltage, or a hybrid system for machining workpieces using an electrically driven tool. The electrical processing equipment can be designed as either a handheld or stationary machine tool. Typical machine tools in this context are hand-held or bench drills, rotary hammers, screwdrivers, impact drills, planers, angle grinders, orbital sanders, polishing machines, nailers, and the like. Electrical processing equipment also includes electrically driven garden and construction equipment such as lawnmowers, string trimmers, pruning saws, rotary tillers and trenchers, blowers, and the like. Furthermore, the invention is applicable to household appliances such as vacuum cleaners, blenders, etc., or to electrically powered vehicles, in particular e-bikes, e-scooters, etc.

[0008] In a further training project, it is specified that the electric motor is a brushless DC motor and that the power electronics incorporate an inverter bridge circuit. This circuit pulse-width modulates the motor voltage signal for controlling the brushless DC motor in such a way that the switching ratio of the motor voltage signal is always 100%. A constant PWM with a maximum switching ratio of 100% offers the particular advantage of maximum energy efficiency combined with minimal EMI.

[0009] If the electrical processing device is supplied with mains voltage, the converter circuit is designed to include an AC / DC converter that dynamically adjusts the target value of the intermediate circuit voltage when the supply voltage is a maximum permissible AC voltage from a stationary power supply network or AC generator for the operation of the processing device. A maximum permissible AC voltage is understood to mean, in particular, that it is determined by the design and configuration of the drive train of the electrical processing device or that it is based on the maximum permissible value of the country- or region-specific mains voltage of a single-phase system (e.g., approximately 240 to 252 V for Europe) for the market in which the processing device is intended. Accordingly, the AC voltage generated by an AC generator will also be based on the country- or region-specific mains voltage.The term "alternating current generator" refers specifically to a device that uses an internal combustion engine, a comparable energy converter, or an energy storage device in conjunction with an inverter to generate an alternating voltage that corresponds to the relevant country- or region-specific grid voltage.

[0010] If the supply voltage is lower than the maximum permissible AC voltage of a stationary power supply network or AC generator, an AC / DC converter in the converter circuit with integrated power factor correction generates the intermediate circuit voltage and dynamically adjusts its setpoint. This allows the electrical processing device to be operated very efficiently even with lower mains voltages, which is particularly advantageous.

[0011] Furthermore, a logic circuit is designed to regulate the target value of the DC link voltage in real time. This allows the DC link voltage to be adjusted promptly to the value necessary for maximum efficiency of the machining tool, depending on the operating point, power requirements, permissible temperature, rotational speed, torque, or other parameters of the workpiece. The target value of the DC link voltage can be set, for example, by a preferably analog control loop of the control electronics of the machining tool. Alternatively, a fixed, preset control element, particularly a potentiometer, can also be used to specify the target value.

[0012] If the supply voltage is provided by the battery voltage of at least one removable battery pack, the converter circuit includes a DC / DC converter that dynamically adjusts the target value of the intermediate circuit voltage. To supply the power to the electrical processing tool with the battery voltage, at least one electromechanical interface is provided on the tool housing for tool-free removal of a removable battery pack. The removable battery pack has a correspondingly complementary electromechanical interface. These interfaces allow the removable battery pack and the electrical processing tool to be detachably connected by force and / or form-fit. A connection that can be detached and reattached without tools is understood to mean, in particular, a connection that can be made and detached by hand.The precise design of the electromechanical interfaces with their mechanical guide elements for force-locking and / or form-locking connections and the electrical contacts used for energy and / or data transmission is not the subject of this invention. A person skilled in the art will select a suitable embodiment for the electromechanical interfaces depending on the power and / or voltage class of the electrical processing device and / or the interchangeable battery packs, so this will not be discussed in further detail.

[0013] The battery voltage can be generated by a plurality of interchangeable battery packs connected in series and / or parallel, which are inserted into a corresponding number of electromechanical interfaces of the electrical processing device. The invention thus enables not only the optional use of mains voltage or an interchangeable battery pack to power the processing device; in the case of multiple electromechanical interfaces, a varying number of interchangeable battery packs can be used depending on the availability of the interchangeable battery packs, the required power consumption, and the desired operating time. Furthermore, the invention advantageously enables, under appropriate boundary conditions, the operation of the processing device with interchangeable battery packs of different voltage classes or battery voltages.

[0014] The voltage class or battery voltage of a battery pack is determined by the connection (parallel or series) of the individual energy storage cells integrated into the pack and is generally an integer multiple (>= 1) of the voltage of the individual energy storage cells. An energy storage cell is typically designed as a galvanic cell with a configuration in which one cell terminal is located at one end and another at the opposite end. Specifically, the energy storage cell has a positive terminal at one end and a negative terminal at the opposite end. Preferably, the energy storage cells are designed as lithium-based cylindrical cells, e.g., Li-ion, Li-polymer, Li-metal, or the like. However, Ni-Cd, Ni-MH cells, or other suitable cell types can also be used.For common lithium-ion energy storage cells with a cell voltage of 3.6 V, examples of voltage classes are 3.6 V, 7.2 V, 10.8 V, 14.4 V, 18 V, 36 V, etc. The DC voltage values ​​depend primarily on the typical cell voltages of the energy storage cells used. For example, pouch cells and / or cells with a different electrochemical composition may have voltage values ​​that differ from those of exchangeable battery packs equipped with lithium-ion cells. The invention is not dependent on the type and design of the energy storage cells used, but can be used in conjunction with any exchangeable battery packs that utilize prismatic cells, pouch cells, or the like instead of cylindrical cells.

[0015] Additionally, the converter circuit can be integrated into the housing of the processing device as part of the drive train. This allows for a particularly compact design combined with optimized cooling and reduced EMI emissions.

[0016] Alternatively, the converter circuit can be designed as a separate adapter, independent of the processing device, which can be inserted into at least one electromechanical interface for the interchangeable battery pack of the processing device without tools. This allows the DC link voltage to be dynamically adjusted even for battery-powered processing devices where this is not provided by design. Furthermore, it is conceivable that a processing device normally only operable with interchangeable battery packs could also be operated with mains voltage via a suitably designed adapter. Preferably, the adapter has a communication interface and / or electrical coding that identifies the processing device for setting the target value for the DC link voltage.This allows the operator of the processing device to use the adapter for different processing devices very easily, without having to worry about the optimal setpoint. Examples of implementation Drawing

[0017] The invention is described below with reference to the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. 6 is explained by way of example, whereby identical reference symbols in the figures indicate identical components with the same function.

[0018] They show: Fig. 1: a schematic representation of a first embodiment of an electrical processing device designed as a battery-powered impact wrench, Fig. 2: a block diagram for the energy supply of an electric motor designed as a three-phase EC motor of the battery-powered impact wrench according to Fig. 1, Fig. 3 a schematic representation of a second embodiment of the electrical processing device designed as a hybrid-powered demolition hammer, Fig. 4: a block diagram for the energy supply of the electric motor of the demolition hammer, designed as a three-phase EC motor, according to Fig. 3. Fig. 5: a block diagram of a third embodiment for the power supply of the electrical processing device and Fig. 6: a block diagram of a fourth embodiment for the power supply of the electrical processing device. Description of the exemplary implementations

[0019] Fig. Figure 1 shows an example of an electric power tool 10 designed as a battery-powered impact wrench with an electric motor 12. The impact wrench has a housing 14 with a handle 16 and a tool holder 18. For independent power supply, it can be mechanically and electrically connected via a corresponding electromechanical interface 20 on the housing 14 to a complementary electromechanical interface 20 of an interchangeable battery pack 22. In this example, the interchangeable battery pack 22 supplies the impact wrench with a voltage U, which is defined as a battery voltage. DC from 18 V DC supply voltage U SHowever, the invention can also be applied with particular advantage – as explained below – to electric processing tools 10 with interchangeable battery packs 22 of other voltage classes. Furthermore, it should be noted that the invention is not limited to impact wrenches or hand-held power tools in general, but – as already mentioned at the outset – can be applied to various mains-powered and / or mains-powered electric processing tools.

[0020] The housing 14 contains, by way of example, the electric motor 12, powered by the interchangeable battery pack 22, along with a gear unit 24 including a clutch and an impact mechanism 26. The gear unit 24, the impact mechanism 26, and the tool holder 18 together form an output unit 28, which is driven by a motor shaft 30 of the electric motor 12. The impact mechanism 26 is designed, by way of example, as a rotary impact mechanism that generates sudden, high-intensity rotational impulses and transmits them to the tool holder 18, which serves to accommodate an interchangeable tool 32. Since the output unit 28 is not essential to the invention as such, it will not be discussed in detail here. The possible embodiments are well known to those skilled in the art.

[0021] The electric motor 12 is designed as a three-phase EC motor and can be controlled via a main switch 34 of the impact wrench, i.e., it can be switched on and off and its speed and / or torque can be changed. For this purpose, the electric motor 12 is supplied with a pulse-width modulated motor voltage signal U by an inverter bridge circuit 36 ​​of a power electronics unit 38. M A control or regulation electronics unit 40 controls the individual power transistors of the inverter bridge circuit 36 ​​according to a signal specified by the travel of the main switch 34 to generate the PWM voltage U. MThe control electronics 40 can be, for example, a microcontroller, DSP, ASIC, or the like. The inverter bridge circuit 36 ​​comprises various power transistors (e.g., bipolar transistors, field-effect transistors, IGBTs, or the like), which are preferably connected as an H6 bridge. Depending on the design of the electric motor 12, other configurations of the inverter bridge circuit 36 ​​are also conceivable, e.g., as an H-bridge, B6 bridge, or the like.

[0022] The housing 14 of the cordless impact wrench also includes an intermediate circuit electronics 42, which is supplied from the battery voltage U provided by the inserted interchangeable battery pack 22. DC a rectified intermediate circuit voltage U IC for supplying the power electronics 38 and the electric motor 12. The electric motor 12, the power electronics 38 and the DC link electronics 42 together form a drive train 44, which - as in Fig. 1 indicated - can consist of locally separated components. Alternatively, it is also conceivable that the drive train 44 is partially or completely integrated into a stator pack 46 of the electric motor 12 (compare Fig. 2) is included. This allows the drive train 44 to be designed as a single, compact module, preferably utilizing the stator stack 46 as a common heat sink. Furthermore, the particularly compact design of the drive train 44 enables reduced EMI emissions. Since the various design options for the electric motor 12, the power electronics 38, and the control electronics 40 are known to those skilled in the art, they will not be discussed in detail here.

[0023] According to the invention, a converter circuit 48 is connected upstream of the intermediate circuit electronics 42, which is derived from the battery voltage U. DC a dynamically adjustable setpoint of the intermediate circuit voltage U ICThis provides a particularly advantageous way to optimize the operation of the impact wrench. To this end, the voltage range in which the impact wrench can be operated is increased, so that its performance no longer depends on a deviation from the ideal voltage. The motor voltage signal U is particularly preferred. M for controlling the EC motor in such a way as to depend on the adapted intermediate circuit voltage U IC The converter circuit is pulse-width modulated, ensuring its clock ratio is always 100% to achieve maximum energy efficiency combined with minimal EMI. The converter circuit 48 can be configured either separately from the DC link electronics 42 and thus from the drive train 44, or alternatively as part of the drive train 44.

[0024] The setpoint of the intermediate circuit voltage U can be determined by means of a logic circuit 50 of the control electronics 40. ICIn real time, depending on the operating point of the EC motor with regard to its power requirements, permissible temperature, speed, torque, or similar parameters, and depending on the workpiece being machined, the value is adjusted to ensure maximum efficiency of the impact wrench. The target value of the DC link voltage U can also be adjusted. IC The setpoint can be specified by a preferably analogous control loop of the power electronics 38. Alternatively, a fixed preset control element 52, in particular a potentiometer, is also conceivable for setting the setpoint.

[0025] In Fig. Figure 2 is a block diagram for the energy supply of the electric motor 12 of the battery-powered impact wrench, which is designed as a three-phase EC motor. Fig. 1 shown. As already mentioned Fig. As described in Figure 1, the electric motor 12, the power electronics 38, and the DC link electronics 42 form the drive train 44 of the cordless impact wrench. The power electronics 38 are controlled by the control electronics 40 to adjust the speed and / or torque of the electric motor 12 such that a pulse-width modulated motor voltage signal U generated by the power electronics 38 is used. MThe invention sets a rotor 56, rigidly connected to the motor shaft 30 and equipped with permanent magnets, into rotational motion by the three phases of a stator winding 54 wound on the stator core 46. Furthermore, the electric motor 12 has sensors (not shown) for determining the speed and position of the rotor 56, which provide the corresponding sensor signals for the control electronics 40. However, the invention is not explicitly limited to three-phase, brushless DC motors, but can also be applied to other types of electric motors 12, such as synchronous motors or universal motors.

[0026] The drive train 44 is powered by the interchangeable battery pack 22 inserted into the electromechanical interface 20. The target value of the intermediate circuit voltage U is thereby... IC from the applied battery voltage U DCThe converter circuit 48 is dynamically adjusted by means of a DC / DC converter 58. In a particularly preferred manner, the clock ratio of the pulse-width modulated motor voltage signal U is adjusted such that M always equals 100%. Additionally, the DC link voltage U is smoothed, either automatically or unautomatically. IC by means of the intermediate circuit stage 42, which in the simplest case consists of at least one capacitor. In the illustrated embodiment, the converter circuit 48 is designed separately from the drive train 44. However, it is also conceivable that it is an integral part of the drive train 44.

[0027] Fig. Figure 3 shows another embodiment of the electric processing device 10 in the form of a demolition hammer. A key difference from the battery-powered impact wrench according to Fig. 1 consists of the mechanical design of the output unit 28, comprising the gear unit 24, the impact mechanism 26, and the tool holder 18, and the performance of the demolition hammer in its power supply. The demolition hammer is designed as a hybrid device that can be supplied either via a mains cable 60 with energy from a stationary power grid or AC generator and / or via two interchangeable battery packs 22 that can be inserted into corresponding electromechanical interfaces 20 located laterally on the housing 14. In this way, the drive train 44, comprising the electric motor 12 (designed as an EC motor), the power electronics 38, and the DC link electronics 42, can be supplied. This drive train, corresponding to the output unit 28, is a different type of drive train compared to the rotary impact wrench. Fig. The drive unit 44 belongs to a significantly higher performance class. A detailed description of the output unit 28 and the insert tool 32 held in the tool holder 18 will be omitted here, as these are of minor importance to the invention. Although the drive train 44 is designed for higher performance levels corresponding to the output unit 28, its basic structure does not otherwise differ from previously known solutions in the art.

[0028] In the case of two 18 V interchangeable battery packs 22 connected in series, for example, the resulting battery voltage U DC of 36 V DC. Analogous to the first embodiment, the converter circuit 48 is connected upstream of the intermediate circuit electronics 42 in order to convert the battery voltage U DC a dynamically adjustable setpoint of the intermediate circuit voltage U ICto provide for optimized operation of the demolition hammer. Is the demolition hammer alternatively or additionally powered via the 60 mains cable with a mains voltage U? AC1 If supplied with, for example, approximately 230 to 240 V, the converter circuit 48 adjusts the target value of the intermediate circuit voltage U. IC correspondingly dynamically. A more detailed description of the dynamic adjustment using the converter circuit 48 will follow with reference to Fig. 4. The motor voltage signal U used to control the EC motor M This can therefore be based on the dynamically adjusted intermediate circuit voltage U IC such that its clock ratio is always 100%, in order to achieve maximum energy efficiency in conjunction with minimal EMI.

[0029] Switching between the power supply modes can be done either manually via a selector switch 62 operated by the user and / or automatically by means of a sensor 64 on the demolition hammer. Switching via a human-machine interface (HMI) 66 located on a handle 16 of the demolition hammer or via an app connected to a communication module (not shown) of the demolition hammer is also conceivable. In this case, the control electronics 40 can evaluate a request signal from the selector switch 62, the sensor 64, the HMI 66, and / or the app to switch between the power supply modes via the logic circuit 50. The request signal can be generated, for example, via a cover flap 68 for a mains interface 70 of the demolition hammer. This flap is closed when powered by the interchangeable battery pack 22 and open when the mains power is supplied by a plugged-in mains connector 72 of the mains cable 60.The position of the cover flap 68 is detected by means of the sensor 64, for example in the form of a reed contact or microswitch, and the corresponding request signal for operation with the mains voltage U is sent. AC1 sent to the control electronics 40. It is also conceivable that the sensor 64 directly detects the applied voltage. Operation with the mains voltage U AC1 Despite the inserted interchangeable battery packs, it has priority over operation with battery voltage U. DCAlternatively, it is also conceivable that the energy supply with the highest performance takes priority, since very powerful interchangeable battery packs 22 sometimes have a higher current delivery capacity than a supply via a stationary power grid or an AC generator. This can simplify the use of the corresponding hybrid-powered demolition hammer for the operator, as they do not have to switch to the respective energy source themselves. Furthermore, the prioritization of the mains voltage U AC1 , so that the inserted interchangeable battery pack 22 is not unnecessarily discharged. Additionally, it can be provided that in the case of power supply to the demolition hammer with the mains voltage U AC1 A replaceable battery pack 22, inserted into the electromechanical interface 20, is charged. Thus, in the event of use of the demolition hammer in a location where there is no mains voltage U, power is available. AC1A charged 22-watt spare battery pack is available.

[0030] In Fig. 4 is a block diagram of the power supply of the demolition hammer according to Fig. 3 shown, whereby the drive train 44, despite its higher performance, is in its basic design similar to that of the rotary impact wrench from the Fig. 1 and Fig. 2 corresponds. Therefore, it will not be discussed again here. Regarding the switching between energy supply types, please refer to the explanations in [reference to relevant section]. Fig. 3 referred. If the power supply of the drive train 44 is provided via the two interchangeable battery packs 22 inserted into the electromechanical interfaces 20, the respective battery voltages U are DC1 and U DC2 from, for example, 18 V by means of two DC / DC converters 58 of the converter circuit 48 to the resulting battery voltage U DCfrom 36 V (e.g. by a series connection of the two interchangeable battery packs 22) in order to determine the target value of the intermediate circuit voltage U on this basis IC to adapt dynamically.

[0031] Is the power supply provided via network interface 70 with an alternating voltage U that is the maximum permissible for operating the demolition hammer? AC1 , so it suffices to set the intermediate circuit voltage U IC Before dynamic adjustment, the converter circuit 48 is rectified by means of a rectifier 72. Is the supply voltage U S a voltage that is in relation to the maximum permissible alternating voltage U AC1 lower alternating voltage U AC2 of a stationary power supply network or AC voltage generator, an AC / DC converter with integrated power factor correction circuit 74 generates the dynamically adjusted intermediate circuit voltage U ICThus, the demolition hammer can also be operated very effectively at lower mains voltages within the optimal range. If one of the AC voltages U is present at the mains interface 70... AC1 or U AC2 If this occurs, it is detected by means of sensor 64 and compared to the battery voltage U. DC Prioritized. The rectified and dynamically adjusted intermediate circuit voltage U IC The signal is then smoothed by means of the regulated or unregulated intermediate circuit electronics 42. In the simplest case, the intermediate circuit electronics 42 consist of at least one capacitor.

[0032] An automatic switchover from battery to mains operation can also be provided if, in particular when the demolition hammer is powered by several series-connected interchangeable battery packs 22, a sudden temperature increase occurs in one of the inserted interchangeable battery packs 22. A similar situation is conceivable if there is an abrupt drop in the battery voltage U. DCor if the voltage is outside a permissible range. Furthermore, the logic circuit 50 can be configured such that it prevents the use of the demolition hammer if two interchangeable battery packs 22 of different voltage classes are inserted. In the case of an electrical processing device 10 with more than two electromechanical interfaces 20, it can also be provided that the logic circuit 50 only connects interchangeable battery packs 22 of the same voltage class in parallel, in order to prevent interchangeable battery packs 22 of a higher voltage class from being unnecessarily partially discharged by interchangeable battery packs 22 of a lower voltage class. For this purpose, the converter circuit 48 preferably includes several DC / DC converters 58 for the different battery voltages or a controllable DC / DC converter 58 for setting them to the same intermediate circuit voltage U. IC on.

[0033] In Fig. Figure 5 shows a block diagram of a third embodiment for supplying power to a purely mains-powered electrical processing device 10. The third embodiment differs from the previous embodiment primarily in that the converter circuit 48 does not include DC / DC converters. Furthermore, the AC / DC converter with integrated power factor correction circuit 74 can be optionally provided, depending on whether the processing device 10 is operated with a voltage higher than the maximum permissible AC voltage U. AC1 lower alternating voltage U AC2must be able to be supplied. Depending on the intended application of the electrical processing device 10, a flexible design of the converter circuit 48 is thus possible through appropriate modularity, for example by omitting certain hybrid-specific components if the processing device 10 is intended only for pure mains operation or pure battery operation, or if it is intended exclusively for a specific mains and / or battery voltage U. AC1 , U AC2 , U DC to be operated. A detailed description of the block diagram shown will be omitted, as it would otherwise essentially be the circuit from Fig. 4 corresponds to.

[0034] Instead of a solution integrated in the electrical processing device 10, the converter circuit 48 can be implemented according to a fourth embodiment according to Fig. Alternatively, the adapter 76 can also be designed as a separate adapter 76 from the processing device 10. For this purpose, the adapter 76 preferably has two different electromechanical interfaces 20, a first of which is essentially identical to the electromechanical interface 20 of the interchangeable battery pack 22 and a second of which is essentially identical to the electromechanical interface 20 of the processing device 10. Thus, the adapter 76 can be detachably inserted into the electromechanical interface 20 of the processing device 10 without tools via its first electromechanical interface 20, and the interchangeable battery pack 22 can be inserted into its second electromechanical interface 20. In the illustrated embodiment, the adapter 76 has three second electromechanical interfaces 20 for receiving three interchangeable battery packs 22.The individual battery voltages U are converted via the DC / DC converters 58 integrated in the converter circuit 48. DC1 , U DC2 , U DC3 resulting battery voltage U DC linked. In the case of a processing device 20, which is connected as standard via its electromechanical interface 20 to a battery voltage U DC If the system is supplied with, for example, 18 V, the three inserted interchangeable battery packs 22 are connected in parallel by the converter circuit 48. This enables dynamic adjustment of the intermediate circuit voltage U. IC also for processing device 10, for which this was not originally intended.

[0035] Alternatively, it is also conceivable that in this way a processing device 10, which is normally only operable by means of interchangeable battery packs 22, could be operated via an analogous to Fig. The adapter 76, designed for 5, can also be operated with a mains voltage. Preferably, the adapter 76 has a communication interface 78 and / or an electrical coding 80, via which the processing device 10 can be identified to determine the permissible battery voltage U. DC and to determine the setpoint for the intermediate circuit voltage U ICThe information from the electrical encoding 80 can be exchanged with the processing device 10 in a particularly preferred manner via the first electromechanical interface 20. For this purpose, the electrical encoding 80 can, for example, be configured as an encoding resistor in the adapter 76 and / or in the processing device 10, the resistance value of which can be read by the control electronics 40 of the processing device 10 or by a processor (not shown) of the adapter 76 and compared with a lookup table. The evaluation can then be performed via the communication interface 78. Thus, the operator of the processing device 10 can use the adapter 76 for different battery-powered processing devices 10 without having to worry about the optimal setpoint and the permissible battery voltage U. DC having to do that.

[0036] Finally, it should be noted that the examples shown do not apply to the Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5 to Fig. 6 is still limited to the aforementioned voltage values ​​and / or the absolute number of electromechanical interfaces 20 or of interchangeable battery packs 22. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 2535149 A2

[0003] EP 4297934 A1

[0003] EP 2991807 A1

[0003] EP 3070028 A1

[0003]

Claims

[1] Electric machining device (10) with a housing (14), an output mechanism (38) for a tool (32) for machining a workpiece, an electric motor (12) for driving the output mechanism (38), an intermediate circuit electronics (42) for generating a rectified intermediate circuit voltage (U) IC ) from a supply voltage (U S ) of the processing device (10) and a power electronics unit (38) for controlling the electric motor (12) by means of a voltage derived from the intermediate circuit voltage (U IC ) generated motor voltage signal (U M ), wherein the power electronics (38), the intermediate circuit electronics (42) and the electric motor (12) form a drive train (44) which is incorporated in the housing (14) with at least part of the output mechanism (28), characterized by , that a converter circuit (48) is connected upstream of the intermediate circuit electronics (42), which is derived from the supply voltage (U S) a dynamically adjustable setpoint of the DC link voltage (U IC ) provides. [2] Electrical processing device (10) according to claim 1, characterized by , that the electric motor (12) is a brushless DC motor and that the power electronics (38) has an inverter bridge circuit (36) which converts the motor voltage signal (U) M ) for controlling the brushless DC motor in such a way as to depend on the adapted intermediate circuit voltage (U) IC ) pulse width modulated, such that a clock ratio of the motor voltage signal (U M ) is always 100%. [3] Electrical processing device (10) according to any one of the preceding claims, characterized by , that the converter circuit (48) has an AC / DC converter (72) which determines the setpoint of the intermediate circuit voltage (U) IC ) dynamically adjusts when the supply voltage (U S ) a maximum permissible alternating voltage (U) for the operation of the processing device (10)AC1 ) of a stationary power supply network or AC generator. [4] Electrical processing device (10) according to any one of the preceding claims, characterized by , that the converter circuit (48) has an AC / DC converter with integrated power factor correction circuit (72) which reduces the intermediate circuit voltage (U IC ) generates and dynamically adjusts its setpoint when the supply voltage (U S ) a voltage higher than the maximum permissible alternating voltage (U) AC1 ) lower alternating voltage (U AC2 ) of a stationary power supply network or AC generator. [5] Electrical processing device (10) according to any one of the preceding claims, characterized by , that a logic circuit (50), preferably a control or regulation electronics (40), determines the setpoint of the intermediate circuit voltage (U) IC ) in real time. [6] Electrical processing device (10) according to any one of the preceding claims 1 to 4, characterized by , that the setpoint of the intermediate circuit voltage (U IC ) can be specified by an analog control loop of the control or regulating electronics (40) or a fixed preset control element (52), in particular a potentiometer. [7] Electrical processing device (10) according to any one of the preceding claims, characterized by , that the housing (14) of the processing device (10) has at least one electromechanical interface (20) for the tool-free detachable mounting of at least one interchangeable battery pack (22). [8] Electrical processing device (10) according to claim 7, characterized by , that the supply voltage (U S ) by a battery voltage (U DC ) of at least one included interchangeable battery pack (22) and the converter circuit (48) has a DC / DC converter (58) which determines the target value of the intermediate circuit voltage (U IC) dynamically adjusts. [9] Electrical processing device (10) according to any one of the preceding claims, characterized by , that the converter circuit (48) is included as part of the drive train (44) in the housing (14) of the processing device (10). [10] Electrical processing device (10) according to claim 7, characterized by , that the converter circuit (48) is designed as an adapter (76) separate from the processing device (10), which can be inserted into the at least one electromechanical interface (20) of the processing device (10) without tools. [11] Electrical processing device (10) according to claim 10, characterized by , that the adapter (76) has a communication interface (78) and / or an electrical coding (80) via which the processing device (10) can be identified for setting the target value for the intermediate circuit voltage (U) IC ). [12] Electrical processing device (10) according to any one of the preceding claims, characterized by , that the electrical processing device (10) is a hand-held power tool, in particular an electrically hybrid powered hand-held power tool.

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