Abstract: A power tool with an impact mechanism and that is controlled based on a drive angle from impacting. The power tool includes a housing, a brushless direct current (DC) motor within the housing, an impact mechanism, and an output drive device. The brushless DC motor includes a rotor coupled to a motor shaft to produce a rotational output. The impact mechanism includes a hammer coupled to the motor shaft, and an anvil that receives impacts from the hammer and drives an output device. The power tool further includes a position sensor that senses a position of the rotor and a controller coupled to the position sensor. The controller detects an impact of the impact mechanism, calculates a drive angle of the anvil caused by the impact based on output from the position sensor, and controls the brushless DC motor based on the drive angle.

Abstract: A speed control assembly for an appliance includes a bracket and a cam that is slidably coupled with the bracket and has an engagement edge. A lever is operably coupled with the cam and is configured to move the cam along the bracket. A slider is fixedly coupled with the bracket and a magnet is disposed adjacent the engagement edge. A ball bearing that is in magnetic communication with the magnet is configured to be selectively engaged with one of a plurality of retention spaces that are defined by the engagement edge of the cam. A sensor is configured to detect a position of the magnet.

Abstract: Power tool devices described herein include a housing, a power source interface, a field effect transistor within the housing connected between the power source interface and a load of the power tool device, and an electronic processor coupled to the field effect transistor. The electronic processor is configured to control the field effect transistor to drive the load and measure a voltage at a terminal of the field effect transistor. The electronic processor is also configured to determine the current flowing through the field effect transistor based on the voltage without using a shunt resistor.

Abstract: Disclosed herein are orthopedic impact tools and methods of use thereof. The orthopedic impact tools can include a housing, a tube assembly, a reverse impact plate, an anvil and an impact mechanism. The housing can include a hand grip portion and an impact mechanism housing portion. The tube assembly can include a first tube portion and a second tube portion. The reverse impact plate can be disposed in between the first tube portion and the second tube portion. The anvil can include a forward impact surface. The impact mechanism can include a motor, a piston, a ram, and a rotary to linear conversion mechanism drivingly connecting the motor to the piston. The piston can be disposed within the first tube portion and the ram can be disposed in the second tube portion and movable into contact between the reverse impact plate and the forward impact surface.

Abstract: A work tool includes a motor, a driving mechanism, a body housing and a handle. The driving mechanism is configured to perform an operation of linearly reciprocating the tool accessory along a driving axis extending in a front-rear direction. The handle includes a grip part extending substantially in an up-down direction, and a battery-mounting part provided on a lower side of the grip part. An upper end portion of the handle is connected to a rear end portion of the body housing via an elastic member so as to be movable relative to the body housing. A lower end portion of the handle is connected to the rear end portion of the body housing so as to be rotatable relative to the body housing, around a rotation axis extending in a left-right direction. The rotation axis is located on a lower side of the battery-mounting part.

Abstract: An automated craniotomy opening apparatus includes a drilling apparatus with a drilling tip, at least one drilling apparatus positioning device, a detection device, and a computer processor that automatically controls the drilling apparatus, the positioning device, and the detection device. A method for automated opening of craniotomies includes, under automatic control of a computer processor, drilling into a skull for a predetermined distance and determining when there is a conductance drop near the drilling tip that indicates skull breakthrough. If the conductance is not below a predetermined threshold, drilling continues iteratively manner until conductance is below the threshold. A craniotomy pattern may be predetermined and automatically drilled under control of the processor. A cranial window may be created by drilling along a path that interpolates between holes to form the circumference of the window. Determining conductance may include use of an impedance detection circuit.

Abstract: A speed control assembly for an appliance includes a bracket. The bracket is aligned with a slot defined by an appliance body. A cam is slidably coupled with the bracket and has an engagement edge positioned at an angle relative to the bracket. A lever is operably coupled with the cam and extends through the slot. The lever is configured to move the cam along the bracket. A slider is fixedly coupled with the bracket. A magnet housing is operably coupled with the slider and is configured to house a magnet. The magnet housing defines a recess. A ball bearing is magnetically coupled with the magnet housing and is positioned within the recess. The ball bearing is configured to be selectively engaged with the engagement edge of the cam. A Hall-effect sensor configured to detect the position of the magnet.

Abstract: An adapter for connecting a single voltage battery pack to a power tool, the single voltage battery pack configured to output only one voltage and provided with a single voltage battery interface, the power tool detachable coupled with a multi-voltage battery pack and provided with a power tool interface, the single voltage battery interface being not coupleable to the power tool interface, the adapter comprising a housing, an input interface disposed in the housing and provided for electrically and mechanically coupling with the single voltage battery interface of the single voltage battery pack, an output interface disposed in the housing and provided for electrically and mechanically coupling with the power tool interface of the power tool, the input interface electrically connected with the output interface, wherein the power tool can be powered by the single voltage battery pack through the adapter.

Abstract: Herein a chainsaw (1) is disclosed comprising a guide bar (3) and a chain (5) moveably arranged around the guide bar (3). The chainsaw (1) comprises an motor (9) comprising a motor shaft (11), wherein the motor (9) is configured to drive the chain (5) via the motor shaft (11). The chainsaw (1) further comprises a tension estimation arrangement (13) configured to sense a load on the motor shaft (11), and configured to estimate the tension of the chain (5) around the guide bar (3) on the basis of the sensed load on the motor shaft (11). The present disclosure further relates to a method of estimating tension of a chain (5) of a chainsaw (1).

Abstract: A controller of a machine tool includes: a position command calculation unit which calculates a position command for relatively moving a workpiece and a tool; an oscillation operation execution determination unit which analyzes a machining program and which determines whether or not an oscillation operation of relatively oscillating the workpiece and the tool is performed in a machining block; an oscillation operation intermittent execution determination unit which determines, when it is determined that the oscillation operation is performed, in the machining block, based on the state of the machine tool, whether the oscillation operation is enabled or disabled so as to determine whether or not the oscillation operation is intermittently performed; an oscillation command calculation unit which calculates, when it is determined that the oscillation operation is enabled, an oscillation command for relatively oscillating the workpiece and the tool; and an adder which adds the position command and the oscillation

Abstract: A power tool includes a housing and a sensor, a machine learning controller, a motor, and an electronic controller supported by the housing. The sensor is configured to generate sensor data indicative of an operational parameter of the power tool. The machine learning controller includes a first processor and a first memory and is coupled to the sensor. The machine learning controller further includes a machine learning control program configured to receive the sensor data, process the sensor data using the machine learning control program, and generate an output based on the sensor data using the machine learning control program. The electronic controller includes a second processor and a second memory and is coupled to the motor and to the machine learning controller. The electronic controller is configured to receive the output from the machine learning controller and control the motor based on the output.

Abstract: A power tool comprises a housing and an electric motor disposed in the housing. A rotary output is driven by the motor. Electronic sensor configured to sense operating parameters of the power tool includes a voltage sensor arranged to detect the voltage across the electric motor, a current sensor arranged to detect the current through the tool, and a speed sensor arranged to detect the angular velocity ? of the output spindle. Electronic control apparatus is configured to determine from the operating parameter output signals the torque M of the rotary output and control the angular velocity of the rotary output in response to the calculation of the torque of said rotary output.

Abstract: An electric working machine in one aspect of the present disclosure includes: a motor; a controller for controlling driving of the motor; a first setter; and a second setter. The first setter is operated for setting, as a control method for the motor, which is usable by the controller, one of control methods preliminarily registered. The second setter is operated for setting, as a control method for the motor, which is usable by the controller, at least one of the control methods settable via the first setter.

Abstract: An electric working machine in one aspect of the present disclosure includes: a motor, a manipulator, a setter, and a controller. The setter sets first control characteristics preliminarily registered. The first control characteristics are set to achieve a rotational speed of the motor from a minimum rotational speed to a maximum rotational speed with a manipulating range of the manipulator, which is 50% or less of an effective manipulating range thereof.

Abstract: Systems and methods for increasing productivity in a production activity are provided. A machine for accomplishing the production activity generates units of output, which are monitored by a data acquiring device. An expected earnings rate is generated by a processor based on expected production parameters and earnings data. An evaluated earnings rate is generated by the processor based upon the actual output and the earnings data. The evaluated earnings rate and expected earnings rate is displayed on a display.

Abstract: An electric working machine in one aspect of the present disclosure includes a driving device, a controller, a control power source, and an operation state determiner. The control power source includes a first converter and a second converter. The control power source transitions to a first conversion state when the operation state determiner determines that the controller is in a control operation state. The control power source in the first conversion state supplies a first control current to the controller. The control power source transitions to a second conversion state when the operation state determiner determines that the controller is in a low power operation state. The control power source in the second conversion state (i) stops operation of the first converter, and (ii) supplies a second control current to the controller.

Abstract: In an electric driver configured such that a driver bit is coupled to a drive output shaft of an electric motor via a clutch mechanism to perform screw tightening operations, an automatic screw tightening control method and a device are provided such that an appropriate screw tightened state in a screw tightening operation can be confirmed and determined, simply and reliably. In a screw tightening operation by an electric driver, at start of a predetermined screw tightening operation, a rotation amount of an electric motor at a clutch operation time by a clutch mechanism is detected, this rotation amount is set to be a target rotation amount and in the subsequent screw tightening operations, a rotation amount of the electric motor at the clutch operation time is detected and compared with the target rotation amount, respectively, so that acceptability of the respective screw tightened states is determined.

Abstract: A computerized method of machining a workpiece including, prior to machining the workpiece, establishing, based on empirical data obtained from machining activity at an earlier time, an historical mapping indicating pairings of depth of cut and rpm at which undesirable chatter (UDC) did not occur during machining activity at an earlier time using at least one given type of milling machine, at least one given type of cutting tool and at least one given type of workpiece material, prior to commencing machining of the workpiece, programming a machine tool to machine the workpiece using a given type of milling machine, a given type of cutting tool and a given type of workpiece material at at least one depth of cut and rpm, which, based on the historical mapping, avoid UDC and operating the machine tool in accordance with the programming to machine the workpiece.

Abstract: An electronic control unit is configured to operate an electric motor from a rechargeable battery pack. The control unit has a circuit board with electronic components for driving the electric motor. Furthermore, an electrical braking circuit having a braking resistor and also a braking switch is provided. The receiving surface of the circuit board is spatially divided into a first surface region and a second surface region. The first surface region serves to receive electronic components; the second surface region serves to receive the braking resistor, wherein the braking resistor is configured as a conductor track which is formed on the circuit board.

Abstract: An apparatus (100) to trace pile set during pile driving comprises a panel (110) for attachment to a pile (150); a holding mechanism (120) to hold a writing instrument (160) against the panel (110) to trace the pile set for series of blows during the pile driving; a sliding mechanism (130) to provide lateral movement across the panel (110) for the holding mechanism (120) after each blow during the pile driving; and a platform (140) to allow the sliding mechanism (130) to slide freely in horizontal direction.

Abstract: A teleoperational medical system for performing a medical procedure in a surgical field includes a teleoperational assembly having a plurality of motorized surgical arms configured to assist in a surgical procedure. It also includes an input device configured to receive an input to move all the arms of the plurality of motorized surgical arms to a pre-established position. A processing system is configured to receive the input form the input device and output control signals to each arm of the plurality of motorized surgical arms to move each arm to the pre-established position.

Abstract: A method of controlling motor velocity in a surgical instrument is disclosed. The surgical instrument includes a displacement member, a motor coupled to the displacement member, a control circuit coupled to the motor, a position sensor coupled to the control circuit, and a timer coupled to the control circuit. The method includes receiving a first position of a displacement member from a position sensor, starting a timer, advancing the displacement member to a second position by setting a motor velocity to a first velocity, receiving the second position from the position sensor, stopping the timer when the displacement member reaches the second position, receiving elapsed time from the timer, wherein the elapsed time is the time taken by the displacement to move from the first position to the second position, and controlling, by the control circuit, velocity of the motor based on the elapsed time.

Abstract: A system includes at least one hand-held power tool and at least one electrotechnical product. The power tool includes a housing with a handle, a drive motor arranged in the housing, and a first interface configured to receive information from at least one second external interface and/or to transmit information to the at least one second external interface. The housing of the hand-held power tool and a housing of the electrotechnical product each have a receiving opening. The first interface is removably arranged in a selected one of the receiving openings. The receiving openings are releasably sealed by corresponding covers. The covers close the housings to the outside.

Abstract: It is an object to provide a novel technique for releasing an intervening member of a driving member. A representative screwdriver is provided with a motor and a driving mechanism. The driving mechanism has a spindle, a lock sleeve, rollers, a driving gear, a retainer and a spring receiver. When driven with the rollers held between the lock sleeve and the driving gear, the spindle is rotated in a normal direction. The lock sleeve has an inclined part and the retainer has an inclined part. The lock sleeve and the retainer move with respect to each other in the axial direction and the circumferential direction by sliding contact between the inclined parts. This relative movement in the circumferential direction is utilized to release the holding of the rollers.

Abstract: A drill rig includes a drawworks having a drum operably connected to a drive system and a brake. A drill string extends from the drum of the drawworks, along a derrick, to a block and tackle arrangement holding a travelling block so that operation of the drawworks causes the drum to release or retract the drill string. A travelling block controller controls the operation of the drawworks. An interlock sensor senses a sensed parameter, and the sensed parameter is at least one of a drill rig parameter, a drawworks parameter, or a travelling block controller parameter. An interlock signal generated by the interlock sensor is reflective of the sensed parameter. An interlock operably connected to the travelling block controller receives the interlock signal and disables operation of at least one of the travelling block controller or the drawworks if the interlock signal meets a predetermined criteria.

Abstract: A power tool is provided including a tool housing, an electric motor disposed inside the tool housing, a power interface facilitating a connection to a power source, a plurality of power components arranged to modulate a supply of power from the power interface to the electric motor, a user-actuated input unit providing an analog signal corresponding to a desired rotational speed of the electric motor, and a control unit is receiving the analog signal from the user-actuated input unit. The control unit includes a controller configured to control a switching operation of the power components based on the analog signal to regulate an amount of electric power being supplied to the electric motor, and an input detection unit configured to generate an ON/OFF signal to turn on the controller based on detection of a prescribed change in the analog signal indicative of an initial actuation of the user-actuation unit.

Abstract: The present disclosure involves a novel way of using drilling vibrations generated by the deformation of a rock formation in response to forces acting on the rock formation, where the forces are related to a drill bit and/or drilling fluid system, to identify the nature and occurrence of fractures, fracture swarms and other mechanical discontinuities (boundaries) such as bedding planes and/or faults that offset or otherwise separate rock formations with different mechanical rock properties.

Abstract: A method of processing a workpiece comprises identifying processing locations on the workpiece, drilling a first hole at one of the processing locations using a rotary drive, sensing a flow of fluid while drilling, generating an operation signal based on the flow, comparing the duration interval of the operation signal to a predetermined temporal value, and drilling a different hole at a different processing location based on the duration interval and the temporal value.

Abstract: In one aspect, a method for automatically controlling a height of an implement of an agricultural work vehicle relative to a ground surface may include monitoring, with one or more computing devices, the height of the implement relative to the ground surface. The method may also include determining, with the one or more computing devices, an implement height error by comparing the height of the implement with a predetermined target height. The method may also include calculating, with the one or more computing devices, a proportional signal based on the implement height error raised to a power greater than one. The method may also include adjusting, with the one or more computing devices, the height of the implement relative to the ground surface based on the proportional signal.

Abstract: A computerized method of machining a workpiece including, prior to machining the workpiece, establishing, based on empirical data obtained from machining activity at an earlier time, an historical mapping indicating pairings of depth of cut and rpm at which undesirable chatter (UDC) did not occur during machining activity at an earlier time using at least one given type of milling machine, at least one given type of cutting tool and at least one given type of workpiece material, prior to commencing machining of the workpiece, programming a machine tool to machine the workpiece using a given type of milling machine, a given type of cutting tool and a given type of workpiece material at at least one depth of cut and rpm, which, based on the historical mapping, avoid UDC and operating the machine tool in accordance with the programming to machine the workpiece.

Abstract: A system includes an accessory tool selected from a group consisting of a casing unit, a cementing unit, and a drilling unit; and a genset mounted to the accessory tool and comprising: a fluid driven motor having an inlet and an outlet for connection to a control swivel of the system; an electric generator connected to the fluid driven motor; a manifold having an inlet for connection to the control swivel and an outlet connected an accessory tool actuator; and a control unit in communication with the electric generator and the manifold and comprising a wireless data link.

Abstract: A motor control apparatus controlling a motor driving a machine tool includes, an abnormal load detecting unit that detects an abnormal load by monitoring a load of the motor, a retract amount storing unit that stores a plurality of retract amounts used when the machine tool performs a retract operation in response to detection of an abnormal load by the abnormal load detecting unit, a retract amount switching unit that switches a retract amount selected from the plurality of retract amounts in accordance with a result of determination of whether the machine tool is processing or not, and a retract amount adding unit that adds a retract amount selected by switching of the retract amount switching unit to an instruction value indicative of a movement amount of the machine tool.

Abstract: A system, method and computer-readable medium for fine-tuning speed selection for reducing machine chatter. The system includes circuitry configured to determine a predetermined speed of the machine. The circuitry identifies a stability lobe based on the predetermined speed of the machine and selects a first set of fine-tuning speeds from a range of machine speeds corresponding to the determined stability lobe. Further, the circuitry causes the machine to operate at one or more of the first set of fine-tuning speeds.

Abstract: A handheld tool having a battery interface is described, in which a provision is made for the handheld tool to have at least one measuring device interface, which is provided to receive at least data containing measuring information of a handheld tool add-on measuring device.

Abstract: A power tool includes a motor, an impact mechanism, an output unit, a circuit board, a housing, and a power cord. The circuit board includes a power-source circuit board configured to convert alternate current into direct current and a control circuit board. The housing includes a body section, a board accommodating section, and a handle section. The board accommodating section accommodates the circuit board. The handle section has one end portion connected to the body section and another end portion connected to the board accommodating section. The power cord extends from the board accommodating section. The power cord is positioned opposed to the handle section with respect to the board accommodating section. The control circuit board is located at a position close to the handle section in the board accommodating section. The power-source circuit board is located between the control circuit board and the power cord.

Abstract: An electric screwdriver includes a motor having a motor shaft, a handle housing for accommodating the motor, an output shaft at least partly protruding from the handle housing, a transmission device for enabling the motor shaft to drive the output shaft to rotate around a first axis, an exploring antenna for detecting whether an object is charged, and an operating switch coupled to the handle housing for controlling the motor. The exploring antenna has a front end portion extending beyond the handle housing. The output shaft has an inserting groove, and a ratio of the maximum size of the handle housing to the maximum size of the inserting groove in a radial direction of the output shaft is greater than or equal to 3.9 and less than or equal to 8.

Abstract: According to an aspect of the present invention, there is provided an impact tool including: a motor drivable in an intermittent driving mode; a hammer connected to the motor; an anvil to be struck by the hammer to thereby rotate/strike a tip tool; and a control unit that controls a rotation of the motor by switching a driving pulse supplied to the motor in accordance with a load applied onto the tip tool.

Abstract: A power tool includes a housing, a motor, an output member driven by the motor, and a reaming attachment coupled to the output member. The reaming attachment has a front end portion selectively driven in rotation by the output member to drive a fastener into a workpiece, and a reaming portion selectively driven in rotation by the output member to remove material from an end surface of a conduit. A rotational motion sensor in the housing is operable to detect rotational motion of the housing about an axis. A controller receives a signal indicative of rotational motion from the sensor, determines a direction of the rotational motion of the housing, and drives the motor in a direction corresponding to the direction of rotational motion of the housing.

Abstract: A system includes a power tool having a motor, a drive mechanism mechanically coupled to the motor, and an output element mechanically coupled to the drive mechanism. The motor is operable to drive the drive mechanism and the output element. The system also includes a non-motorized sensing tool having a printed circuit board and a sensing element electrically coupled to the printed circuit board. The sensing element is operable to detect an external characteristic and output a signal to the circuit board. The circuit board is operable to condition the signal into a human-comprehensible form. The system further includes a rechargeable battery pack removably and independently coupled to the power tool and the non-motorized sensing tool to power the motor to drive the drive mechanism and the output element when connected to the power tool and the circuit board and the sensing element when connected to the non-motorized sensing tool.

Abstract: A machine tool has a tool retainer for retaining a tool, a motor and a drivetrain which couples the motor with the tool retainer for transmitting a torque. A system pushbutton is coupled with a motor control. When the system pushbutton is activated by a user, the motor control controls the motor in such a way that the motor turns in a first sense of rotation for a duration and then in a sense of rotation opposed to the first sense of rotation. The duration is shorter than 100 ms.

Abstract: A rotary impact tool according to one aspect of the present invention includes a motor, an impact mechanism, a drive unit, an impact detection unit, and a control unit. The control unit reduces a driving force for the motor caused by the drive unit when a count of impacts detected by the impact detection unit has reached a determination count set in advance, which is a value greater than one.

Abstract: Percussion unit, especially for a rotary hammer and/or percussion hammer, comprising a control unit which is designed for open-loop and/or closed loop control of a pneumatic percussion mechanism, and at least one operating condition sensor unit. According to the disclosure, the control unit is designed to detect at least one percussion mechanism parameter depending on measurement values of the operating condition sensor unit.

Abstract: The present invention relates to a restart protection device and a method thereof, wherein the restart protection device is installed in an electric device, and comprises a switch module and a restart protecting module. The restart protecting module is connected between the switch module and a motor of the electric device, used for preventing the current outputted by an external electrical power from directly flowing into the motor when the electric device is restarted. To start the electric device, the user must follow the steps of the restart protection method, such that the unexpected accidents resulted from the sudden restart of the electric device can be effectively prevented.

Abstract: A percussion unit for a rotary hammer and/or percussion hammer includes a control unit that is configured for open-loop and/or closed loop control of a pneumatic percussion mechanism. In at least one operating state in which the control unit changes from an idle mode to a percussion mode, the control unit is configured to adjust at least one operating parameter temporarily to a starting value.

Abstract: A device for regulating an increase in the output torque over time of an electric drive motor, including a monitoring unit for monitoring an operating variable of the electric drive motor, a regulating unit for regulating the operating variable for regulating the increase in output torque over time, a control unit for activating the regulating unit as a function of a time derivation of the monitored operating variable, the regulating unit being designed to be deactivated after a predetermined period of time. A method for regulating an increase in the output torque over time of an electric drive motor is also described. A corresponding tool and a computer program having program code for carrying out the method are also described.

Abstract: A multi-purpose electric tool has a motor, an impact block, a detection assembly configured to detect the position and the movement state of the impact block, and a main control circuit board configured to control whether the motor is powered off upon reaching a preset state according to the detected information of the detection assembly. In the control method, the detection assembly feeds back the detected information to the main control circuit board, if the impact block is not impacting reciprocatingly, the main control circuit board performs torque control according to whether the preset state is reached; and if the impact block is impacting reciprocatingly, the main control circuit board enables the motor to output in a normal mode which does not limiting the current.

Abstract: It is an object of the invention to provide a technique for enhancing the operability of a power tool. A representative screwdriver 100 is provided which has a motor 110 and a driving mechanism 120. The driving mechanism 120 has a rotation transmitting mechanism including a driving cam 137 and a driven cam 157, and a cam engagement state is switched by movement of the spindle 150 in a longitudinal direction of the spindle. The position of the spindle 150 in the longitudinal direction is detected by a detecting mechanism 162 that is disposed on the opposite side of the rotation transmitting mechanism from a front end region in the longitudinal direction of the spindle 150. A controller 180 controls the rotation speed of the motor 110 based on the detection result of the detecting mechanism 162 and drives the motor 110.

Abstract: A tooling system that includes a drive unit configured to provide rotational force to a tool member. The tool member is attached at a mount on the drive unit. A camera associated with the drive unit is aligned to capture a target on the tool member. The data is sent to a controller that identifies the tool member based on the target. The controller determines whether the tool member is correct for performing an operation on a work piece. If the tool member is correct, the controller may set one or more operating parameters on the drive unit. If the controller determines that the tool member is not correct, the drive unit is disabled. Further, a signal may be sent to inform an operator of the issue.

Abstract: A torque applying system includes a torque applying tool having a motor and rotating output spindle, a torque sensor that measures an instantaneous torque exerted by the output spindle during a fastening cycle, and a controller operatively connected to the tool to control the tool's rotational speed during the fastening cycle. The controller is programmed to control the tool's rotational speed to be [(?F??C)/t]/r, wherein t is a time constant of speed control, ?F is a target final torque for the fastening cycle, and r is a torque rate.

Abstract: The invention relates to a portable, handheld work apparatus such as a trimmer, a cut-off machine, a chain saw or the like, having a motor (5, 33) to drive a rotating, exchangeable work tool (13). A control unit (15) serves to control the operation of the motor (5, 33). The control unit (15) determines the rotational speed (n) and/or the power (P) of the motor (5, 33). According to the invention, the motor (5, 33) can be operated in a first operating mode (I) with reduced rotational speed (n0) and/or power (P0) and in at least a second operating mode (II) with an increased rotational speed (n1) and/or power (P1). In dependence on a release signal, the control uses exclusively the first operating mode (I) for a limited operation and the second operating mode (II) for an expanded operation.