MACHINE TOOL AND METHOD FOR OPERATING A MACHINE TOOL

Description

State of the art

[0001] A machine tool with a tool and an impact device having an impact drive unit for generating and transmitting an impact force to the tool has already been proposed. EP 2 036 680 A2 discloses such a machine tool. Disclosure of the invention

[0002] The invention is based on a machine tool with a tool and with an impact device which has an impact drive unit for generating and transmitting an impact force to the tool.

[0003] According to the invention, the impact drive unit comprises at least one impact drive module for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force to the tool via a fluid.

[0004] Preferably, the machine tool is designed as a portable handheld power tool, for example, as an impact drill and / or as an impact driver and / or as a rotary hammer and / or as a demolition hammer and / or as a chisel hammer and / or the like. However, the machine tool could also be designed as a stationary machine tool, for example, as a pillar drill or the like, or as a machine tool integrated into a drilling robot.

[0005] The impact device is a part, preferably a subassembly, of the machine tool and comprises at least the impact drive unit. The impact device can also comprise further units and / or elements. The impact drive unit is provided for generating and transmitting an impact force to the tool and, for this purpose, comprises at least one impact drive module. The impact drive module is provided for generating the impact force based on the magneto-hydraulic effect, according to which an electrically conductive fluid located in a magnetic field is accelerated in a flow direction perpendicular to the magnetic field and perpendicular to the electric field due to the Lorentz force when an electrical voltage is applied between two electrodes which generate an electric field oriented perpendicular to the magnetic field.

[0006] The fluid used in the impact drive module to generate and transmit the impact force is an electrically conductive fluid and contains free charge carriers, such as free electrons and / or ions, which are set in motion when a power source is connected and conduct an electrical current. Preferably, the machine tool has at least one reservoir for storing the fluid, from which the fluid can be drawn by means of the impact drive module. Alternatively or additionally, it is conceivable for the fluid to circulate in a fluid circuit of the impact drive unit, with the impact drive unit having corresponding fluid lines for this purpose.

[0007] An "operating state" is understood to mean a state in which the machine tool and / or the impact drive unit is / are ready for operation and / or is / are in operation. This operation may be a drilling operation and / or an impact drilling operation and / or an impact operation.

[0008] In this document, numerals such as "first" and "second," which precede certain terms, serve only to distinguish between objects and / or to correlate objects with each other and do not imply a total number and / or ranking of the objects. In particular, a "second object" does not necessarily imply the presence of a "first object."

[0009] "Intended" should be understood as specifically configured, specifically designed, and / or specifically equipped. The fact that an object is intended for a specific function should preferably be understood as meaning that the object fulfills and / or performs this specific function in at least one application and / or operating state.

[0010] The design according to the invention advantageously makes it possible to provide a particularly compact machine tool. Furthermore, compared to conventional machine tools, for example impact drills, in which the impact force is generated via a locking disc and transmitted to the drilling tool via the drill chuck, or hammer drills, in which the impact force is generated via a pneumatic impact mechanism and transmitted directly to the drilling tool, the number of rotating and / or mechanically force-locking components of the impact drive unit can advantageously be reduced, preferably minimized. This advantageously reduces wear. Furthermore, noise emissions can advantageously be reduced.

[0011] Furthermore, it is preferably proposed that the impact drive module comprises at least one flow channel for the fluid, at least two magnetic elements arranged outside the flow channel, and at least two control electrodes connected to the flow channel, wherein the magnetic elements and the control electrodes are provided to cause a Lorentz force in the fluid to generate the impact force. This advantageously enables the impact force to be generated using the magnetohydrodynamic effect with simple technical means. The flow channel has walls made of an electrically insulating material. The flow channel could have a constant cross-section. It is also conceivable for the flow channel to have a cross-section that tapers towards the tool. This advantageously makes it possible to increase the fluid pressure in the flow channel and thus the impact force.The magnetic elements of the impact drive module are preferably arranged on opposite sides outside the flow channel. A first magnetic element of the magnetic elements has, at least temporarily or permanently, a first magnetic polarity, and a second magnetic element of the magnetic elements has, at least temporarily or permanently, a second magnetic polarity opposite to the first magnetic polarity, so that a magnetic field exists between the magnetic elements, which is preferably oriented substantially perpendicular to a main extension direction of the flow channel. A "main extension direction" of an object is understood to mean a direction that runs parallel to a longest edge of a smallest geometric cuboid that just completely encloses the object. The magnetic elements could be designed as permanent magnets.It is also conceivable for the magnetic elements to be designed as electromagnets. The control electrodes are preferably embedded in the channel walls of the flow channel and, when the impact drive unit is in operation, are in contact with the fluid within the flow channel. The control electrodes could be embedded in the channel walls of the flow channel in such a way that they protrude into the flow channel. However, the control electrodes are preferably embedded in the channel walls of the flow channel in such a way that they each terminate flush with an inner side of a channel wall of the flow channel. When a voltage is applied to the control electrodes, an electric field is generated in the flow channel which is oriented at least substantially perpendicular to the magnetic field generated by the magnetic elements, such that a Lorentz force is generated in the fluid and the fluid in the flow channel is accelerated in the direction of the Lorentz force.In this document, "at least substantially perpendicular" is to be understood as an orientation of a direction which, with a reference direction, encloses an angle between 85° and 95°, in particular an angle between 86° and 94°, advantageously an angle between 87° and 93°, particularly advantageously an angle between 88° and 92°, preferably an angle between 89° and 91° and particularly preferably an angle of 90°.

[0012] Furthermore, it is preferably proposed that the machine tool have a control and / or regulating unit connected to the control electrodes of the impact drive module for controlling and / or regulating the impact drive unit by means of a control current. This advantageously enables targeted control and / or regulation of the impact force. The impact force generated by the impact drive unit and / or a generated impact pulse and / or a generated impact frequency can advantageously be variably and specifically adjusted. A "control and / or regulating unit" is understood to mean a unit with at least one control electronics unit. "Control electronics" is understood to mean a unit with a processor unit and a memory unit, as well as with an operating program stored in the memory unit. The control current can be a direct current or an alternating current.Preferably, the control and / or regulating unit is connected to the respective control electrodes of each impact drive module of the impact drive unit and is provided with a control current for controlling the impact drive modules. The control and / or regulating unit could be provided to control and / or regulate various impact drive modules of the impact drive unit by using control currents that have the same magnitude and / or the same phase position. It is also conceivable that the control unit is provided to use different control currents that differ from one another in terms of magnitude and / or phase position for controlling and / or regulating some or all of the impact drive modules of the impact drive unit.

[0013] Furthermore, it is preferably proposed that the control and / or regulating unit is provided to generate a reversal of the flow direction of the fluid in the flow channel by changing the flow direction of the control current. Such a configuration can advantageously enable particularly efficient operation of the machine tool. A particularly intensive impact effect and / or high impact frequency can advantageously be generated. Preferably, the control and / or regulating unit is provided to generate alternating pumping and suction of the fluid by repeatedly changing the flow direction of the control current. Preferably, a frequency of a change in the flow direction by the control and / or regulating unit and thus an impact frequency of the generated impact force can be adjusted by a user. Preferably, the impact drive unit has at least one return channel for returning the fluid to the flow channel.

[0014] Furthermore, it is preferably proposed that the control and / or regulating unit be provided to control the impact drive module with a pulsed control current in order to generate pressure waves in the fluid. This advantageously allows a greater impact force and / or impact frequency to be generated. The control and / or regulating unit can be provided to control the impact drive module and / or at least one other impact drive module of the impact drive unit with a pulsed control current in order to generate pressure waves in the fluid.The control and / or regulating unit can be provided, in particular depending on an operating mode of the machine tool selectable by a user, to use at least one electrical control pattern to control the impact drive module and / or the at least one further impact drive module, wherein the pulsed control current of the electrical control pattern can, for example, have a sinusoidal or rectangular waveform or another temporal profile that appears appropriate to a person skilled in the art. The control and / or regulating unit can be provided to use the same electrical control pattern to control the impact drive module and the further impact drive module. Alternatively, the control and / or regulating unit can also be provided to control some or all of the impact drilling modules of the impact drive unit with their own separate electrical control pattern.

[0015] Furthermore, it is preferably proposed that the impact drive unit comprise at least one further impact drive module, which is configured substantially identically to the impact drive module, wherein the impact drive module and the further impact drive module are hydraulically interconnected such that the forces generated in the respective impact drive modules add up to the impact force and / or that the fluid flow rates add up. Such a configuration can advantageously generate a particularly high impact force.In addition to the impact drive module and the additional impact drive module, the impact drive unit can have at least one additional impact drive module, which can be configured essentially identically to the impact drive module and can be hydraulically interconnected with the impact drive module and the additional impact drive module such that the forces generated in the respective impact drive modules add up to the impact force. In principle, the impact drive unit can have any number of hydraulically interconnected impact drive modules necessary to generate a specific impact force. Preferably, the impact drive module and the additional impact drive module are electrically interconnected in series.

[0016] Furthermore, it is preferably proposed that the impact drive module and the additional impact drive module are hydraulically connected in series. This advantageously enables a particularly precise adjustment of the impact force strength. Preferably, the impact drive module and the additional impact drive module are electrically and hydraulically connected in series. When several impact drive modules are electrically and hydraulically connected in series, the current strength through all impact drive modules is the same, but the pressure contributions of the impact drive modules are added together. This means that for an assumed target pressure value, this can be achieved either with one impact drive module and a high current strength or with several impact drive modules electrically and hydraulically connected in series with a current strength divided by the number of impact drive modules.Consequently, by means of impact drive modules connected electrically and hydraulically in series, the current intensity and thus advantageously the power loss and / or a cable cross-section and / or a component stress and / or the like can be reduced.

[0017] In a further advantageous embodiment, it is proposed that the impact drive module and the additional impact drive module be hydraulically connected in parallel. This advantageously allows larger impact pulses to be generated, since the flow of the fluid and thus the amplitude of the fluid velocity increases. It is also conceivable for the impact drive unit to have a combination of impact drive modules hydraulically connected in series and hydraulically connected in parallel. For example, the impact drive unit could have the impact drive module and the additional impact drive module, which could be hydraulically connected in parallel, an additional impact drive module, which could be hydraulically connected in series with the impact drive module, and a further additional impact drive module, which could be hydraulically connected in series with the additional impact drive module.Many other ways of hydraulically interconnecting several impact drive modules of the impact drive unit are conceivable which appear sensible to the expert.

[0018] The fluid could, for example, be a solution with free charge carriers, such as a saltwater solution or the like. However, in an advantageous embodiment, it is proposed that the fluid be a metal and / or a metal alloy that is liquid and / or at least substantially incompressible under standard conditions. Such a configuration can advantageously enable particularly efficient generation and transmission of the impact force. Preferably, the fluid formed as a metal and / or a metal alloy is both liquid and at least substantially incompressible under standard conditions. "Standard conditions" here means a temperature of 0°C and an ambient pressure of 1.01325 bar.In this context, "at least substantially incompressible" means that the fluid formed as a metal and / or metal alloy has a bulk modulus of at least 5 GPa, advantageously at least 10 GPa, preferably at least 15 GPa, more preferably at least 20 GPa, and particularly preferably at least 25 GPa. The fluid formed as a metal and / or metal alloy could, for example, be mercury or a mercury alloy, such as the eutectic mercury-thallium alloy with a mass content of 8.5% thallium. Preferably, the fluid is formed as a non-toxic metal and / or a non-toxic metal alloy that is liquid under standard conditions and / or at least substantially incompressible.Suitable non-toxic metal alloys could, for example, be alloys of alkali metals, in particular alloys of sodium and potassium, which are liquid under standard conditions at a potassium mass content of between 45% and 89% and form a eutectic at mass contents of 22% sodium and 78% potassium. The fluid is preferably in the form of a non-toxic, essentially incompressible metal alloy of gallium, indium, and tin, which is liquid under standard conditions and is available under the brand name Galinstan and is particularly preferably present in a eutectic composition with mass contents of 68.5% gallium, 21.5% indium, and 10% tin. Alternatively, the fluid could also be in the form of another metal and / or metal alloy that is liquid under standard conditions and / or at least essentially incompressible, as deemed appropriate by a person skilled in the art. The fluid preferably has a high thermal conductivity.Preferably, in addition to generating and transmitting the impact force, the fluid is also provided for distributing and / or dissipating heat that occurs in an operating state of the machine tool. For example, the fluid can be provided for distributing and / or dissipating heat that occurs in the operating state due to electrical power loss of electrical and / or electronic components of the machine tool and / or due to frictional energy between mechanically moving components of the machine tool, for example shafts and the like. For this purpose, the machine tool can have corresponding cooling channels by means of which the fluid is guided past the components of the machine tool to be cooled and / or through the components to be cooled in the operating state.In particular, the fluid has a thermal conductivity of at least 5 W / mK, advantageously a thermal conductivity of at least 10 W / mK, particularly advantageously a thermal conductivity of at least 15 W / mK, preferably a thermal conductivity of at least 20 W / mK and particularly preferably a thermal conductivity of at least 25 W / mK.

[0019] The impact drive module and / or the additional impact drive module could be provided to transmit the impact force directly to the tool via the fluid. In an advantageous embodiment, however, it is proposed that the impact drive unit has a transmission unit with at least one transmission element, in particular a piston and / or bellows, for transmitting the impact force from the impact drive module to the tool. This can advantageously improve the targeted transmission of the impact force. The impact drive module and / or the additional impact drive module are hydraulically connected to the transmission element of the transmission unit, either directly or indirectly via at least one additional transmission element of the transmission unit. The impact drive module and / or the additional impact drive module could be arranged outside the transmission unit.It is also conceivable that the impact drive module and / or the further impact drive module are arranged within the transmission unit, in particular in the transmission element.

[0020] Furthermore, it is preferably proposed that the machine tool have a sensor module for detecting at least one current flow parameter of the fluid based on the magnetohydrodynamic effect, wherein the sensor module is designed at least substantially identically to the impact drive module and is hydraulically connected to it. Such a configuration can advantageously enable self-sensing. The current flow parameter of the fluid can be, for example, but is not limited to, the current flow direction of the fluid in the flow channel and / or a flow velocity of the fluid in the flow channel. Preferably, the control and / or regulating unit is directly or indirectly connected to sensor electrodes of the sensor module. Preferably, the control and / or regulating unit is provided to adapt an electrical control curve based on data from the sensor module.Preferably, the control and / or regulating unit is provided to electronically regulate and preferably optimize an impact behavior of the impact drive unit based on data from the sensor module.

[0021] Furthermore, it is preferably proposed that the machine tool has an analysis unit connected to the sensor module for detecting at least one operating parameter based on data from the sensor module. Such a configuration can advantageously improve ease of use. The analysis unit has at least one computing unit, which can be designed, for example, as a microprocessor, for analyzing the data from the sensor module. The analysis unit is preferably connected to the control and / or regulating unit or is part of the control and / or regulating unit. The control and / or regulating unit is preferably provided to control and / or regulate the impact drive unit based on the at least one operating parameter detected by the analysis unit.The operating parameter may, for example, be, but is not limited to, an amount of impact force generated in the impact drive module and / or an amplitude of an impact pulse and / or an amount of an impact frequency and / or the like. It is conceivable that the analysis unit is provided for a further analysis of the tool's effects on the sensor module and for determining at least one further operating parameter.

[0022] For example, the analysis unit could be provided for a frequency analysis of the tool and for determining a further operating parameter, for example, the quality and / or material of a workpiece to be machined by the machine tool and / or the type of tool used and / or wear of the tool and / or a change in the quality and / or material of the workpiece to be machined during a drilling and / or impact operation, for example, impact on reinforcing steel of a concrete wall. This advantageously allows the control parameters of the impact drive unit to be automatically adapted to a current operating situation by the control and / or regulating unit.It is also conceivable for the machine tool to have an output unit, for example a display or the like, for outputting operating parameters determined by the analysis unit and / or further operating parameters to a user. For example, in the operating state of the machine tool, the output unit could provide the user with information about suboptimally set operating parameters, e.g. an impact force that is too high or too low, and / or about the use of an unsuitable and / or worn tool, based on the analyses of the analysis unit. The invention is further based on a method for operating a machine tool, in particular according to one of the previously described embodiments, wherein an impact force is generated and transmitted to a tool of the machine tool.

[0023] According to the invention, the impact force is generated based on the magnetohydrodynamic effect and transmitted to the tool via a fluid. Such a method can advantageously enable particularly efficient, low-wear, and quiet operation of the machine tool. drawing

[0024] Further advantages will become apparent from the following description of the drawings. The drawings illustrate seven exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination.

[0025] They show: Fig. 1 shows a machine tool with a tool and with an impact device in a schematic representation, Fig. 2 shows a schematic side view and a schematic sectional view of an impact drive module of an impact drive unit of the impact device, Fig. 3 shows a schematic view of the impact drive unit with the impact drive module, a further impact drilling module and a control and / or regulating unit, Fig. 4 shows two schematic diagrams illustrating the mode of operation of the impact drive unit, Fig. 5 shows a schematic process flow diagram of a method for operating the machine tool, Fig. 6 shows a further embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation, Fig. 7 shows a further embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation, Fig.Fig. 8 shows a further exemplary embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation, Fig. 9 shows a further exemplary embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation, Fig. 10 shows a further exemplary embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation and Fig. 11 shows a further exemplary embodiment of an impact device of a machine tool, with an impact drive unit in a schematic representation. Description of the embodiments

[0026] Figure 1shows a machine tool 10a with a tool 12a and with an impact device 14a in a schematic representation. In the present exemplary embodiment, the machine tool 10a is designed as an impact drill and the tool 12a is designed, for example, as an impact drill with a cutting edge. In principle, however, the machine tool 10a could also be designed as a different type of machine tool, for example as a hammer drill (not shown) or as a demolition hammer (not shown) or the like. Furthermore, the tool 12a can be designed as another drilling and / or impact tool, for example as a flat chisel. The machine tool 10a can be provided to drive the tool 12a in an impact drilling mode, i.e. to set it both in a rotational movement about its own axis and in an impact movement in the axial direction.Alternatively, the machine tool 10a can also be provided to drive the tool in an impact mode, wherein the tool 12a does not rotate about its own axis and is only driven to perform an impact movement in the axial direction.

[0027] The impact device 14a has an impact drive unit 16a for generating and transmitting an impact force to the tool 12a. The impact drive unit 16a has at least one impact drive module 18a for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force via a fluid 20a (see FIG. Figure 2 ) onto the tool 12a.

[0028] Figure 2shows the impact drive module 18a of the impact drive unit 16a in a schematic side view and in a schematic sectional view along a cutting edge 48a. The impact drive module 18a has at least one flow channel 22a for the fluid 20a. The cutting edge 46a runs perpendicular to a main extension direction 70a of the flow channel 22a. The impact drive module 18a further has at least two magnetic elements 24a, 26a arranged outside the flow channel 22a. The impact drive module 18a also has at least two control electrodes 28a, 30a connected to the flow channel 22a. The control electrodes 28a, 30a are embedded in a wall of the flow channel 22a in such a way that they are flush with an inner side of the wall in order to minimize flow resistance of the fluid 20a.The magnetic elements 24a, 26a and the control electrodes 28a, 30a are provided to create a Lorentz force in the fluid 20a to generate the impact force. In the present case, the magnetic elements 24a, 26a of the impact drive module 18a are designed as permanent magnets, with the magnetic element 24a having a positive magnetic polarity and the magnetic element 26a having a negative magnetic polarity, so that a magnetic field 66a exists between the magnetic elements 24a, 26a, which is oriented perpendicular to the main extension direction 70a of the flow channel 22a. If, in an operating state of the impact drive unit 16a, an electrical voltage is applied to the control electrodes 28a, 30a, an electric field 68a is created, which is oriented substantially perpendicular to the magnetic field 66a. A current flow from the control electrode 28a to the control electrode 30a is created via free charge carriers in the fluid 20a.Due to the field forces of the magnetic field 66a and the electric field 68a, a Lorentz force acts on the charge carriers in the fluid 20a and the fluid 20a is set in motion in the flow channel 22a in the flow direction 36a, which corresponds to the direction of the Lorentz force.

[0029] The fluid 20a is formed as a metal and / or as a metal alloy which is liquid and / or at least substantially incompressible under standard conditions. In the present case, the fluid 20a is formed from a metal alloy which is liquid and at least substantially incompressible under standard conditions, at a temperature of 0°C and an ambient pressure of 1.01325 bar, i.e., has a bulk modulus of at least 5 GPa. In the present case, the fluid is a metal alloy of gallium, indium, and tin, with mass contents of 68.5% gallium, 21.5% indium, and 10% tin, which has a melting point of -19°C and is non-toxic.

[0030] Figure 3shows a schematic view of the impact drive unit 16a. In the present embodiment, the impact drive unit 16a has the impact drive module 18a and at least one further impact drive module 38a. The further impact drive module 38a is designed essentially identically to the impact drive module 18a. The impact drive module 18a and the further impact drive module 38a are hydraulically interconnected such that the forces generated in the respective impact drive modules 18a, 38a add up to the impact force. In the present case, the impact drive module 18a and the further impact drive module 38a are hydraulically interconnected in series, specifically via the flow channel 22a, which hydraulically connects the impact drive module 18a to the further impact drive module 38a.

[0031] The impact drive module 18a and the further impact drive module 38a are electrically connected in series. For this purpose, the control electrode 28a of the impact drive module 18a and a further control electrode 76a of the further impact drive module 38a are electrically connected to each other via a connection 110a.

[0032] The impact drive unit 16a has a transmission unit 40a with at least one transmission element 42a for transmitting the impact force from the impact drive module 18a to the tool 12a. The transmission element 42a is designed as a striking pin, which is mounted in a hammer tube 72a of the transmission unit 40a.

[0033] The machine tool 10a has a control and / or regulating unit 32a connected to the control electrodes 28a, 30a of the impact drive module 18a for controlling and / or regulating the impact drive unit 16a by means of a control current 34a (cf. Figure 4). In the present case, the control and / or regulating unit 32a is indirectly connected to the control electrodes 28a, 30a of the impact drive module 18a and two further control electrodes 74a, 76a of the further impact drive module 38a, specifically via two connection electrodes 106a, 108a of the impact drive unit 16a. The control and / or regulating unit 32a is provided for controlling the impact drive module 18a and the further impact drive module 38a by means of the control current 34a. In the operating state of the impact drive unit 16a, the control current 34a flows from the control and / or regulating unit 16a via the connection electrode 106a to the further control electrode 74a of the further impact drive module 38a. Between the further control electrodes 74a, 76a of the further impact drive module 38a, a further electric field (not provided with a reference symbol) is created due to the free charge carriers in the fluid 20a.Due to the further electric field, the control current 34a flows from the further control electrode 76a via the connection 110a to the control electrode 28a of the impact drive module 18a. The electric field 68a is created between the control electrodes 28a, 30a of the impact drive module 18a due to the free charge carriers in the fluid 20a (cf. ). Figure 2 ) and the control current 34a flows due to the electric field 68a from the control electrode 30a to the connection electrode 108a and back to the control and / or regulating unit 32a.

[0034] The control and / or regulating unit 32a is provided to control the impact drive module 18a with a pulsed control current 34a in order to generate pressure waves in the fluid 20a. In the present case, the control and / or regulating unit 32a is provided to control the impact drive module 18a and the further impact drive module 38a with a pulsed control current 34a in order to generate pressure waves in the fluid 20a. To control the impact drive module 18a and the one further impact drive module 38a, the control and / or regulating unit 32a can use at least one electrical control pattern, wherein the pulsed control current 34a of the electrical control pattern can, for example, have a sinusoidal or rectangular temporal profile.

[0035] The flow channel 22a of the impact drive module 18a opens into the hammer tube 72a of the transmission unit 40a. In the operating state of the impact drive unit 16a, the transmission element 42a, designed as a striking pin, is pushed forward by the pressure of the fluid 20a acting in the flow direction 36a in the hammer tube 72a, thereby transmitting the impact force from the impact drive module 18a to the tool 12a.

[0036] Figure 4 shows two schematic diagrams illustrating the operation of the impact drive unit 16a. On an abscissa 50a of a left diagram of the Figure 4A current of the control current 34a is plotted in amperes. On an ordinate 52a of the left diagram, a pressure of the fluid 20a in the flow channel 22a is plotted in bar. A straight line 54a, which runs through various measuring points at different current intensities, shows a substantially linear relationship between the current of the control current 34a and the pressure of the fluid 20a in the flow channel 22a. On an abscissa 56a of a right diagram of the Figure 4 The current intensity of the control current 34a is plotted in amperes. On the ordinate 58a of the right-hand diagram, the flow rate of the fluid 20a in the flow channel 22a is plotted in cubic centimeters per second. A series of measured values ​​through which a straight line 60a was drawn refers to the Figure 2shown configuration of the impact drive unit 16a with the impact drive module 18a, which is hydraulically connected in series with the further impact drive module 38a, and shows a substantially linear relationship between the current intensity of the control current 34a and the flow rate of the fluid 20a.

[0037] Figure 5 shows a schematic process flow diagram of a method for operating the machine tool 10a. In the method, an impact force is generated and transferred to the tool 12a of the machine tool 10a. The method comprises at least two method steps 62a, 64a. In a first method step 62a of the method, the impact force is generated based on the magnetohydrodynamic effect. In a second method step 64a of the method, the impact force is transferred to the tool 12a via the fluid 20a.

[0038] In the Figures 6 to 11Six further embodiments of the invention are shown. The following descriptions and the drawings are essentially limited to the differences between the embodiments, whereby with regard to components with the same designation, in particular with regard to 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 Figures 1 to 5 To distinguish the embodiments, the letter a is added to the reference numerals of the embodiment in the Figures 1 to 5 In the examples of the Figures 6 to 11 the letter a is replaced by the letters b to g.

[0039] Figure 6 shows a further embodiment of an impact device 14b of a machine tool 10b (not shown here, cf. Figure 1 ), which can be designed, for example, as an impact drill or a hammer drill.

[0040] Analogous to the previous embodiment, the impact device 14b has an impact drive unit 16b for generating and transmitting an impact force to a tool 12b of the machine tool 10b. The impact drive unit 16b has at least one impact drive module 18b for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force to the tool 12b via a fluid 20b.

[0041] In contrast to the previous exemplary embodiment, the impact drive unit 16b has a sensor module 44b. The sensor module 44b is provided for detecting at least one current flow parameter of the fluid 20b based on the magnetohydrodynamic effect. The current flow parameter of the fluid 20b can be, for example, a current flow direction 36b of the fluid 20b and / or a flow velocity of the fluid 20b. The sensor module 44b is at least substantially identical to the impact drive module 18b and is hydraulically connected to it via a flow channel 22b of the impact drive module 18b.

[0042] The machine tool 10b has an analysis unit 46b connected to the sensor module 44b for detecting at least one operating parameter based on data from the sensor module 44b. The analysis unit 46b is connected to two sensor electrodes 102b, 104b of the sensor module 44b.

[0043] The machine tool 10b has a control and / or regulating unit 32b connected to control electrodes 28b, 30b of the impact drive module 18b for controlling and / or regulating the impact drive unit 16b using a control current (not shown). In contrast to the previous exemplary embodiment, the control and / or regulating unit 32b is directly connected to the control electrodes 28b, 30b of the impact drive module 18b, and there is no electrically conductive connection between the impact drive module 18b and the sensor module 44b.

[0044] In an operating state of the impact drive unit 16b, the fluid 20b in the impact drive module 18b is set in motion in the flow direction 36b based on the magnetohydrodynamic effect and flows from the impact drive module 18b via the flow channel 22b into the sensor module 44b. As the fluid 20b flows through the sensor module 44b, an electric field 68b is created between the sensor electrodes 102b, 104b of the sensor module 44b due to the free charge carriers in the fluid 20b, which is detected and analyzed by the analysis unit 46b. The analysis unit 46b determines at least one operating parameter from the data of the sensor module 44b, for example, an amount of the impact force generated in the impact drive module 18b and / or an amount of an impact frequency and / or the like.

[0045] The impact drive unit 16b has a transmission unit 40b with at least one transmission element 42b for transmitting the impact force from the impact drive module 18b to the tool 12b. The transmission element 42b is designed as a striking pin, which is mounted in a hammer tube 72b of the transmission unit 40b. In contrast to the previous exemplary embodiment, the transmission element 42b is provided for an indirect transmission of the impact force from the impact drive module 18b to the tool 12b. Furthermore, in contrast to the previous exemplary embodiment, the transmission unit 40b has a first further transmission element 78b, which is also arranged in the hammer tube 72b. The first further transmission element 78b of the transmission unit 40b is designed as a striker.

[0046] The flow channel 22b of the impact drive module 18b opens into a hammer tube 72b of the transmission unit 40b.

[0047] In an operating state of the impact drive unit 16b, the first further transmission element 78b designed as a striker is pushed forward by the pressure of the fluid 20b acting in a flow direction 36b in the hammer tube 72b and thereby transmits the impact force to the transmission element 42b designed as a striking pin and thus to the tool 12b.

[0048] Figure 7 shows a further embodiment of an impact device 14c of a machine tool 10c (not shown here, cf. Figure 1 ), which can be designed, for example, as an impact drill or a hammer drill.

[0049] Analogous to the previous embodiments, the impact device 14c has an impact drive unit 16c for generating and transmitting an impact force to a tool 12c of the machine tool 10c. The impact drive unit 16c has at least one impact drive module 18c for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force to the tool 12c via a fluid 20c.

[0050] The impact drive unit 16c has at least one further impact drive module 38c, which is designed essentially identically to the impact drive module 18c. The impact drive module 18c and the further impact drive module 38c are hydraulically interconnected such that the flow rates of the fluid (20c) add up. In contrast to the first embodiment, the impact drive module 18c and the further impact drive module 38c are hydraulically interconnected in parallel. Furthermore, in contrast to the previous embodiments, the impact drive unit 16c has two additional impact drive modules 84c, 86c, each of which is designed essentially identically to the impact drive module 18c.An additional impact drive module 84c is hydraulically connected in series with the impact drive module 18c via a flow channel 22c, so that the forces generated in the additional impact drive module 84c and those generated in the impact drive module 18c by means of the magneto-hydrodynamic effect are added. A further additional impact drive module 86c is hydraulically connected in series with the further impact drive module 38c via a further flow channel 88c, so that the forces generated in the further additional impact drive module 86c and those generated in the further impact drive module 38c by means of the magneto-hydrodynamic effect are added.The flow channel 22c and the further flow channel 88c each open into a hammer tube 72 of a transmission unit 40c of the impact drive unit 16c, so that the flows of the fluid 20c generated by the additional impact drive module 84c and the impact drive module 18c in the flow channel 22c and the further additional impact drive module 86c and the further impact drive module 38c in the further flow channel 88c add up in the hammer tube 72c, and there the impact force acts on a first further transmission element 78c of the transmission unit 40c, which is designed as a striker. With regard to the function of the transmission unit 40c for transmitting the impact force to the tool, reference can otherwise be made to the above explanations regarding the previous exemplary embodiment. Figure 6 be referred to.

[0051] The machine tool 10c has a control and / or regulating unit 32c connected to control electrodes 28c, 30c of the impact drive module 18c for controlling and / or regulating the impact drive unit 16c by means of a control current (not shown). The control and / or regulating unit 32c is indirectly connected to the control electrodes 28c, 30c of the impact drive module 18c via two connection electrodes 106c, 108c of the impact drive unit 16c. The control and / or regulating unit 32c is provided for controlling the impact drive module 18c, the further impact drive module 38c, the additional impact drive module 84c, and the further additional impact drive module 86c by means of a control current (not provided with a reference symbol). The impact drive module 18c and the additional impact drive module 84c are electrically connected in series via a connection 110c.The control unit 32c is connected via the connection electrode 106c to an additional control electrode 94c of the additional impact drive module 84c. In an operating state of the impact drive unit 16c, the control current flows from the control and / or regulating unit 32 via the connection electrode 106c to the additional control electrode 94c of the additional impact drive module 84c. An additional electric field (not provided with a reference symbol) is created between the additional control electrode 94c and an additional control electrode 96c due to the free charge carriers in the fluid 20c. Due to the additional electric field, the control current flows from the additional control electrode 96c via the connection 110c to the control electrode 28c of the impact drive module 18c.An electric field (not provided with a reference symbol) is created between the control electrodes 28c, 30c of the impact drive module 18c due to the free charge carriers in the fluid 20c, and the control current flows due to the electric field from the control electrode 30c to the connection electrode 108c and back to the control and / or regulating unit 32c. The control and / or regulating unit 32c is indirectly connected to further control electrodes 74c, 76c of the further impact drive module 74c via two further connection electrodes 112c, 114c of the impact drive unit 16c. The further impact drive module 38c and the further additional impact drive module 86c are electrically connected in series with one another via a further connection 116c. The control unit 32c is connected via the further connection electrode 112c to a further additional control electrode 98c of the further additional impact drive module 86c.In the operating state of the impact drive unit 16c, the control current flows from the control and / or regulating unit 32c via the further connection electrode 112c to the further additional control electrode 98c of the further additional impact drive module 86c. A further additional electric field (not provided with a reference symbol) is created between the further additional control electrode 98c and a further additional control electrode 100c due to the free charge carriers in the fluid 20c. Due to the further additional electric field, the control current flows from the further additional control electrode 100c via the further connection 116c to the further control electrode 74c of the further impact drive module 38c.Between the further control electrodes 74c, 76c of the further impact drive module 38c, a further electric field (not provided with a reference symbol) is created due to the free charge carriers in the fluid 20c, and the control current flows due to the further electric field from the further control electrode 76c to the connection electrode 114c and back to the control and / or regulating unit 32c.

[0052] Figure 8 shows a further embodiment of an impact device 14d of a machine tool 10d (not shown here, cf. Figure 1 ), which can be designed, for example, as an impact drill or a hammer drill.

[0053] Analogous to the embodiment of the Figures 1 to 5The impact device 14d has an impact drive unit 16d for generating and transmitting an impact force to a tool 12d of the machine tool 10d. The impact drive unit 16d has at least one impact drive module 18d for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force to the tool 12d via a fluid 20d. The impact drive unit 16d has at least one further impact drive module 38d, which is essentially identical to the impact drive module 18d and is hydraulically connected in series with it via a flow channel 22d such that the forces generated in the respective impact drive modules 18d, 38d add up to the impact force.

[0054] Analogous to the first exemplary embodiment, the machine tool 10d has a control and / or regulating unit 32d connected to control electrodes 28d, 30d of the impact drive module 18d for controlling and / or regulating the impact drive unit 16d by means of a control current (not provided with a reference symbol). In the present case, the control and / or regulating unit 32d is indirectly connected via two connection electrodes 106d, 108d to the control electrodes 28d, 30d and two further control electrodes 74d, 76d of the further impact drive module 38d. The impact drive module 18d and the further impact drive module 38d are electrically connected in series. For this purpose, the control electrode 28d of the impact drive module 18d and the further control electrode 76d of the further impact drive module 38d are electrically connected to one another via a connection 110d.

[0055] The impact drive unit 16d has a transmission unit 40d with at least one transmission element 42d for transmitting the impact force from the impact drive module 18d to the tool 12d. The transmission element 42d is designed as a striking pin, which is mounted in a hammer tube 72d of the transmission unit 40d. Analogous to the embodiments of the Figures 6 and 7 the transmission element 42d is provided for an indirect transmission of the impact force from the impact drive module 18d to the tool 12d. In contrast to the embodiments of the Figures 6 and 7The transmission unit 40d has two further transmission elements 78d, 80d, which are also arranged in the hammer tube 72d. A first further transmission element 78d of the transmission unit 40d is designed as an exciter piston. A second further transmission element 80d of the transmission unit 40d is designed as a striker. An air gap 82d is arranged between the first transmission element 78d and the second transmission element 80d. The flow channel 22d of the impact drive module 18d opens into the hammer tube 72d of the transmission unit 40d.

[0056] In an operating state of the impact drive unit 16d, the first further transmission element 80d designed as an exciter piston is pushed forward by the pressure of the fluid 20d acting in a flow direction 36d in the hammer tube 72d and thereby transmits the impact force via the air gap 82d to the second further transmission element 80d designed as a striker, which in turn transmits the impact force to the transmission element 42d designed as a firing pin and thus to the tool 12d.

[0057] Figure 9 shows a further embodiment of an impact device 14e of a machine tool 10e (not shown here, cf. Figure 1 ), which can be designed, for example, as an impact drill or a hammer drill.

[0058] The Figure 9 The embodiment shown represents a combination of the embodiments of the Figures 7 and 8Analogous to the previous embodiments, the impact device 14e has an impact drive unit 16e for generating and transmitting an impact force to a tool 12e of the machine tool 10e. The impact drive unit 16e has, analogous to the embodiment of the Figure 7at least one impact drive module 18e for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force via a fluid 20e to the tool 12e, and at least one further impact drive module 38e, which is designed essentially identically to the impact drive module 18e and is hydraulically connected in parallel with it. Furthermore, the impact drive unit 16e has two additional impact drive modules 84e, 86e, each of which is designed essentially identically to the impact drive module 18e, wherein an additional impact drive module 84e is hydraulically connected in series with the impact drive module 18e via a flow channel 22e, and a further additional impact drive module 86e is hydraulically connected in series with the further impact drive module 38e via a further flow channel 88e.

[0059] Furthermore, the impact drive unit 16e has a transmission unit 40e, which is analogous to the transmission unit 40d from the embodiment of the Figure 8 is trained.

[0060] Analogous to the embodiment of the Figure 7The machine tool 10e has a control and / or regulating unit 32e connected to control electrodes 28e, 30e of the impact drive module 18e for controlling and / or regulating the impact drive unit 16e by means of a control current (not provided with a reference symbol). The control and / or regulating unit 32e is indirectly connected to the control electrodes 28e, 30e of the impact drive module 18e, specifically via two connection electrodes 106e, 108e of the impact drive unit 16e. The control and / or regulating unit 32e is also indirectly connected to further control electrodes 74e, 76e of the further impact drive module 38e, specifically via two further connection electrodes 112e, 114e of the impact drive unit 16e.The control and / or regulating unit 32e is provided for controlling the impact drive module 18e, the further impact drive module 38e, the additional impact drive module 84e and the further additional impact drive module 86e by means of a control current (not provided with a reference symbol). The impact drive module 18e and the additional impact drive module 84e are electrically connected in series with one another via a connection 110e. The further impact drive module 38e and the further additional impact drive module 86e are electrically connected in series with one another via a further connection 116e. With regard to the connection of the control and / or regulating unit 32e with the impact drive modules 18e, 38e, 84e, 86e, reference can otherwise be made to the above description of the . Figure 7 be referred to. Figure 10 shows a further embodiment of an impact device 14f of a machine tool 10f (not shown here, cf. Figure 1), which can be designed, for example, as an impact drill or a hammer drill.

[0061] The Figure 10 The embodiment shown represents a further development of the Figures 1 to 5 Analogous to the embodiment of the Figures 1 to 5 the impact device 14f has an impact drive unit 16f for generating and transmitting an impact force to a tool 12f of the machine tool 10f with at least one impact drive module 18f for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force via a fluid 20f to the tool 12f and at least one further impact drive module 38f, which is designed essentially identically to the impact drive module 18f and is hydraulically connected in series with it via a flow channel 22f such that the forces generated in the respective impact drive modules 18f, 38f add up to the impact force.

[0062] The impact drive unit 16f has a transmission unit 40f which, analogous to the transmission unit 40b in the embodiment of the Figure 6 , at least one transmission element 42f arranged in a hammer tube 72f of the transmission unit 40f and designed as a striking pin for the indirect transmission of the impact force from the impact drive module 18f to the tool 12f and at least one first further transmission element 78f designed as a striker, which is also arranged in the hammer tube 72f. In contrast to the embodiment of the Figure 6The transmission unit 40f has a return channel 90f, which is connected to the hammer tube 72f. In an operating state of the impact drive unit 16f, the fluid 20f is pressed against the first further transmission element 78f, designed as a striker, by the Lorentz forces generated in the impact drive module 18f and the further impact drive module 38f based on the magnetohydrodynamic effect and acting on the free charge carriers in the fluid 20f, so that the latter moves in the flow direction 36f against the transmission element 42f, designed as a striking pin, and thus transmits the impact force from the transmission element 42f to the tool 12f.As soon as the first further transmission element 78f in the hammer tube 72f has moved in the flow direction 36f at least partially over a position at which the return channel 90f is connected to the hammer tube 72f, a part of the fluid 20f flows back into the flow channel 22f via the return channel 90f.

[0063] Analogous to the examples of the Figures 3 and 8The machine tool 10f has a control and / or regulating unit 32f connected to control electrodes 28f, 30f of the impact drive module 18f for controlling and / or regulating the impact drive unit 16f by means of a control current (not provided with a reference symbol). In the present case, the control and / or regulating unit 32f is indirectly connected via two connection electrodes 106f, 108f to the control electrodes 28f, 30f and two further control electrodes 74f, 76f of the further impact drive module 38f. The impact drive module 18f and the further impact drive module 38f are electrically connected in series. For this purpose, the control electrode 28f of the impact drive module 18f and the further control electrode 76f of the further impact drive module 38f are electrically connected to one another via a connection 110f.

[0064] The control and / or regulating unit 32f is provided to generate a reversal of the flow direction 36f of the fluid 20f in the flow channel 22f by changing the direction of the control current. In contrast to the previous embodiments, the impact drive unit 16f is therefore bidirectional. By the control and / or regulating unit 32f reversing the signs of the control voltages applied between the control electrodes 28f, 30f of the impact drive module 18f and the further control electrodes 74f, 76f of the further impact drive module 38f, an electric field 68f between the control electrodes 28f, 30f and a further electric field 92f between the further control electrodes 74f, 76f each act in the opposite direction, so that the Lorentz forces acting on the free charge carriers in the fluid due to the magnetohydrodynamic effect counteract the original and in the Figure 10illustrated flow direction 36f or a reversal of the flow direction 36f of the fluid 20f in the flow channel 22f is generated. This has the result that the fluid 20f is conveyed from the flow channel 22f via the return channel 90f into the hammer tube 72f, whereby the first further transmission element 78f is moved back against the original flow direction 36f in the hammer tube 72f. The control and / or regulating unit 32f is provided to generate a repeated reversal of the flow direction 36f of the fluid 20f in the flow channel 22f by repeatedly changing the flow direction of the control flow. Thus, the control and / or regulating unit 32f is provided to generate an alternating pumping and suction of the fluid 20f, whereby an intensity of the impact effect can be improved.Preferably, a desired frequency of reversing the current direction of the control current and thus an impact frequency of the first further transmission element 78f on the transmission element 42f and thus on the tool 12f can be set by a user via the control and / or regulating unit 32f, which can have a corresponding input element (not shown).

[0065] Figure 11 shows a further embodiment of an impact device 14g of a machine tool 10g (not shown here, cf. Figure 1 ), which can be designed as a hammer drill or a hammer drill. The Figure 11 The embodiment shown represents a combination of the embodiments of the Figures 7 and 10 Analogous to the embodiment of the Figure 7The impact device 14g has at least one impact drive module 18g for generating the impact force based on the magnetohydrodynamic effect and for transmitting the impact force via a fluid 20g to the tool 12g, and at least one further impact drive module 38g, which is designed essentially identically to the impact drive module 18g and is hydraulically connected in parallel with it. Furthermore, the impact drive unit 16g has two additional impact drive modules 84g, 86g, each of which is designed essentially identically to the impact drive module 18g, wherein an additional impact drive module 84g is hydraulically connected in series with the impact drive module 18g via a flow channel 22g, and a further additional impact drive module 86g is hydraulically connected in series with the further impact drive module 38g via a further flow channel 88g.

[0066] Analogous to the embodiment of the Figure 10The impact drive unit 16g has a transmission unit 40g with a transmission element 42g arranged in a hammer tube 72g of the transmission unit 40g and designed as a striking pin for the indirect transmission of the impact force, and at least one first further transmission element 78g designed as a striker, which is also arranged in the hammer tube 72g. Furthermore, the transmission unit 40g has a return channel 90g, which is connected to the hammer tube 72g and is hydraulically connected to the flow channel 22g and the further flow channel 88g.

[0067] Analogous to the examples of the Figures 7 and 9The machine tool 10g has a control and / or regulating unit 32g connected to control electrodes 28g, 30g of the impact drive module 18g for controlling and / or regulating the impact drive unit 16g by means of a control current (not provided with a reference symbol). The control and / or regulating unit 32g is indirectly connected to the control electrodes 28g, 30g of the impact drive module 18g, specifically via two connection electrodes 106g, 108g of the impact drive unit 16g. The control and / or regulating unit 32g is also indirectly connected to further control electrodes 74g, 76g of the further impact drive module 38g, specifically via two further connection electrodes 112g, 114g of the impact drive unit 16g.The control and / or regulating unit 32g is provided for controlling the impact drive module 18g, the further impact drive module 38g, the additional impact drive module 84g and the further additional impact drive module 86g by means of a control current (not provided with a reference symbol). The impact drive module 18g and the additional impact drive module 84g are electrically connected in series with one another via a connection 110g. The further impact drive module 38g and the further additional impact drive module 86g are electrically connected in series with one another via a further connection 116g. With regard to the connection of the control and / or regulating unit 32g with the impact drive modules 18g, 38g, 84g, 86g, reference can otherwise be made to the above description of the . Figure 7The control and / or regulating unit 32g is provided to generate a reversal of a flow direction 36g of the fluid 20g in the flow channel 22g and the further flow channel 88g by changing a flow direction of the control current. Analogous to the embodiment of the Figure 10 The impact drive unit 16g is therefore bidirectional.

Claims

1. Machine tool (10a-g) having a tool (12a-g) and having a striking device (14a-g) that has an impact drive unit (16a-g) for generating and transmitting an impact force to the tool (12a-g), characterized in that the impact drive unit (16a-g) has at least one impact drive module (18a-g) for generating the impact force based on the magnetic hydrodynamic effect and for transmitting the impact force to the tool (12a-g) via a fluid (20a-g).

2. Machine tool (10a-g) according to Claim 1, characterized in that the impact drive module (18a-g) comprises at least one flow channel (22a-g) for the fluid (20a-g), at least two magnetic elements (24a-g, 26a-g) arranged outside the flow channel (22a-g) and at least two control electrodes (28a-g, 30a-g) connected to the flow channel (22a-g), wherein the magnetic elements (24a-g, 26a-g) and the control electrodes (28a-g, 30a-g) are intended to cause a Lorentz force in the fluid (20a-g) in order to generate the impact force.

3. Machine tool (10a-g) according to Claim 2, characterized by an open-loop and / or closed-loop control unit (32a-g) connected to the control electrodes (28a-g, 30a-g) of the impact drive module (18a-g) in order to control the impact drive unit (16a-g) by way of open-loop and / or closed-loop control by means of a control current (34a).

4. Machine tool (10f; 10g) according to Claim 3, characterized in that the open-loop and / or closed-loop control unit (32f; 32g) is intended to produce a reversal of a flow direction (36f; 36g) of the fluid (20f; 20g) in the flow channel (22f; 22g) by changing a current direction of the control current.

5. Machine tool (10a-g) according to Claim 3 or 4, characterized in that the open-loop and / or closed-loop control unit (32a-g) is intended to actuate the impact drive module (18a-g) with a pulsed control current (24a) in order to produce pressure waves in the fluid.

6. Machine tool (10a; 10c-g) according to one of the preceding claims, characterized in that the impact drive unit (16a; 16c-g) has at least one further impact drive module (38a; 38c-g), which is substantially identical to the impact drive module (18a, 18c-g), wherein the impact drive module (18a; 18c-g) and the further impact drive module (38a; 38c-g) are hydraulically interconnected in such a way that the forces generated in the respective impact drive modules (18a; 38a; 18c-g, 38c-g) add up to the impact force and / or that the flows of the fluid (20a, 20c-g) add up.

7. Machine tool (10a; 10d; 10f) according to Claim 6, characterized in that the impact drive module (18a; 18d; 18f) and the further impact drive module (38a; 38d; 38f) are hydraulically interconnected in series.

8. Machine tool (10c; 10e; 10g) according to Claim 6, characterized in that the impact drive module (18c; 18e; 18g) and the further impact drive module (38c; 38e; 38g) are hydraulically interconnected in parallel.

9. Machine tool (10a-g) according to one of the preceding claims, characterized in that the fluid (20a-g) is in the form of a metal and / or in the form of a metal alloy that, under standard conditions, is liquid, and / or at least substantially incompressible.

10. Machine tool (10a-g) according to one of the preceding claims, characterized in that the impact drive unit (16a-g) has a transmitting unit (40a-g) having at least one transmitting element (42a-g), in particular a piston and / or bellows, for transmitting the impact force from the impact drive module (16a-g) to the tool (12a-g).

11. Machine tool (10b) according to one of the preceding claims, characterized by a sensor module (44b) for detecting at least one present flow parameter of the fluid (20b) based on the magnetic hydrodynamic effect, wherein the sensor module (40b) is at least substantially identical to the impact drive module (18b) and is hydraulically connected thereto.

12. Machine tool (10b) according to Claim 11, characterized by an analysis unit (46b) connected to the sensor module (44b) for detecting at least one operating parameter based on data of the sensor module (44b).

13. Method for operating a machine tool (10a-g), in particular according to one of Claims 1 to 12, wherein an impact force is generated and transmitted to a tool (12a-g) of the machine tool (10-g), characterized in that the impact force is generated based on the magnetic hydrodynamic effect and is transmitted to the tool (12a-g) via a fluid (20a-g).