Power tool device and method

Abstract

The invention relates to a power tool device (10), in particular a screwing and / or drilling device, comprising a drive unit (1) for the rotary drive of a tool (2), in particular a drill or a screwdriver blade, wherein the power tool device (10) is designed to carry out an assistance procedure and, as part of the assistance procedure, to repeatedly record a drive variable associated with the rotary drive of the tool during the rotary drive of the tool (2), to obtain drive variable values which represent a temporal curve of the drive variable, to calculate a cumulative sum on the basis of deviation values between the drive variable values and a reference variable, and on the basis of the cumulative sum, to carry out a drive change action in order to change the rotary drive of the tool (2).

Description

[0001] Power tool device and method

[0002] The invention relates to a power tool device, in particular a screwdriving and / or drilling device, comprising a drive unit for rotary driving a tool, in particular a drill or a screwdriver blade. The power tool device is designed to carry out an assistance procedure and, as part of the assistance procedure, to repeatedly record a drive variable associated with the rotary drive of the tool during the rotary drive of the tool in order to obtain drive variable values ​​that represent a temporal profile of the drive variable. The drive variable is, for example, a rotational speed, a torque and / or an electrical drive variable, for example an electrical current.

[0003] With a conventional power tool, for example a conventional cordless screwdriver, the user can set a torque limit to restrict the torque acting on the tool. By selecting the correct value for the torque limit, the user can cause a work process carried out with the power tool, for example a screwing process and / or a drilling process, to stop at a desired working state. When screwing a screw into an object, it is generally desirable to set the torque limit to the screwing-in torque of the screw head, so that the screwing-in process stops when the screw head has reached the surface of the object being processed or is flush with the surface of the object being processed.

[0004] US 8,919,456 B2 describes a method for controlling the operation of a power tool. The current supplied to the electric motor of the power tool is sampled periodically. A slope of a sequence of current measurements is determined using linear regression. Based at least in part on the sequence of current measurements, a torque transmission to an output spindle is interrupted.

[0005] WO 2021 / 244790 A1 describes a power tool device which, during a rotary drive of a tool, determines a change criterion on the basis of at least one detected drive variable and changes the rotary drive of the tool in response to the detected drive variable fulfilling the change criterion.

[0006] One object of the invention is to make it easier for a user to achieve a desired result when working with the power tool device.

[0007] The object is achieved by a power tool device according to claim 1. The power tool device is designed to calculate a cumulative sum on the basis of deviation values ​​between the drive variable values ​​and a reference variable, and to carry out a drive change action on the basis of the cumulative sum in order to change the rotary drive of the tool. A work process to be carried out with the power tool device, for example a screwing process or a drilling process, expediently comprises several (in particular at least two) successive work process phases. A screwing process can, for example, comprise a thread screwing phase in which a thread of a screw is screwed into a processing object while a screw head of the screw is still outside the processing object, and a screw head screwing phase in which the screw head is driven into the processing object.A drilling process comprises, as successive work process phases, for example, a first work process phase in which a drill drills into a first density range and / or a first material of a processing object, and / or a second work process phase in which the drill drills into a second density range and / or a second material of the processing object. The second density range expediently has a different density than the first density range. The second material is expediently a different material than the first material.

[0008] A change from one work process phase to another work process phase, in particular a change from the thread screwing-in phase to the screw head screwing-in phase, and / or the presence of a certain work process phase, in particular the screw head screwing-in phase, leads to a certain behavior, in particular a certain change, in the drive variable. On the basis of the cumulative sum of the deviation values ​​between the drive variable values ​​and the reference variable, this behavior, in particular this change, in the drive variable can be detected by the power tool device, and the power tool device can therefore determine that a certain work process phase, for example the screw head screwing-in phase, is present.

[0009] By means of the drive change action, the power tool device can then change the rotary drive of the tool in particular such that the changed rotary drive matches the determined work process phase, in particular the screw head screwing-in phase, and expediently makes it easier for the user to achieve a desired result in this work process phase. For example, by means of the drive change action, a speed of the rotary drive is reduced, so that it is easier for the user to achieve the desired result - for example, a desired screw-in depth - for example by the user manually ending the screw-in process at the desired screw-in depth - i.e. by operating the power tool device accordingly.

[0010] Advantageous further training is the subject of the subclaims.

[0011] The invention further relates to a method for operating a power tool device, in particular a screwing and / or drilling device, with a drive unit for rotary driving a tool, in particular a drill or a screwdriver blade, comprising the steps of: starting the rotary drive of the tool, carrying out an assistance procedure, and, as part of the assistance procedure: during the rotary drive of the tool, repeatedly recording a drive variable associated with the rotary drive of the tool in order to obtain drive variable values ​​which represent a temporal profile of the drive variable, calculating a cumulative sum on the basis of deviation values ​​between the drive variable values ​​and a reference variable, and on the basis of the cumulative sum, carrying out a drive change action in order to change the rotary drive of the tool.

[0012] The method is expediently carried out with the described power tool device and / or is designed in accordance with a further development of the power tool device.

[0013] Further exemplary details and exemplary embodiments are explained below with reference to the figures.

[0014] Figure 1 is a schematic representation of a power tool device,

[0015] Figure 2 a screw in three different screwing states,

[0016] Figure 3 is a diagram with a torque signal, a current signal and a rotational speed signal,

[0017] Figure 4 shows the power tool device with an attachment,

[0018] Figure 5 shows the power tool device with a mobile device and

[0019] Figure 6 is a flowchart of a method for operating the power tool device.

[0020] Figure 1 shows a power tool device 10, which is embodied, by way of example, as a screwdriving and / or drilling device. The power tool device 10 comprises a drive device 6 and, by way of example, a tool 2 attached to the drive device 6. The drive device 6 is embodied as a handheld device. The drive device 6 is, for example, a drill / screwdriver, in particular a cordless drill / screwdriver. By way of example, the drive device 6 is embodied in a T-shape. Furthermore, the drive device can be embodied in a pistol-shaped manner.

[0021] The drive device 6 has a handle portion 14 that the user can grasp with his or her hand to carry and guide the drive device 6. The handle portion 14 is expediently oriented with its longitudinal axis vertically.

[0022] The drive device 6 further comprises a shaft section 15. The tool 2 is arranged at the front end of the shaft section 15. A shaft 9 expediently extends through the shaft section 15. The shaft section 15 is oriented with its longitudinal axis horizontally, for example.

[0023] The drive device 6 further comprises an energy storage section 16, which is arranged, for example, at the bottom of the handle section 14. The energy storage section 16 comprises an energy storage device 17, for example a battery.

[0024] The power tool device 10 comprises a drive unit 1 for rotary driving the tool 2. The drive unit 1 comprises, for example, an electric motor for rotary driving the tool 2. The tool 2 is, for example, a screwdriver blade. Alternatively, the tool 2 can also be a drill. The power tool device 10 comprises, for example, the shaft 9, via which the tool 2 is coupled to the drive unit 1, in particular the electric motor, so that the tool 2 can be set in a rotary movement by the drive unit 1 via the shaft 9. A conversion unit, for example a gear, is expediently located between the drive unit 1 and the tool 2.

[0025] The power tool device 10, in particular the drive unit 6, comprises an operating device 18, which exemplarily comprises a first operating element 21 and / or optionally a second operating element 22. The operating device

[0026] 18, in particular the first operating element 21, expediently serves to control, in particular to start and / or stop, the rotary drive of the tool 2 provided by the drive unit 1. The first operating element 21 is preferably designed as a trigger button and expediently arranged on the handle section 14. The optionally present second operating element 22 is expediently designed as a rotary switch.

[0027] The power tool device 10 comprises a control unit

[0028] 19, which comprises, for example, a microcontroller. The control unit 19 serves in particular to detect a user input entered by means of the operating device 18, in particular by means of the first operating element 21 and / or the second operating element 22. The control unit 19 is designed to control the drive unit 1 so that it provides the rotary drive of the tool 2. The control unit 19 is designed in particular to control the drive unit 1 taking into account the detected user input.

[0029] The drive device 6 comprises an outer housing 12, in which the control unit 19 and the drive unit 1 are arranged. The handle section 14 is, by way of example, part of the outer housing 12.

[0030] The power tool device 10 is designed to carry out an assistance procedure. The assistance procedure is controlled in particular by the control unit 19. The assistance procedure serves to support a user of the power tool device 10 during a work process, in particular a screwing process or a drilling process, in particular in such a way that the assistance procedure changes the rotary drive of the tool 2 at a suitable time, in particular stops it or reduces the rotational speed. The work process comprises, for example, a plurality of successive work process phases and the assistance procedure serves in particular to detect a change from one work process phase to another work process phase and / or the presence of a specific work process phase and expediently to change the rotary drive of the tool 2 in response to this detection.

[0031] With reference to Figures 2 and 3, a screwing process will be explained below as an example of a work process.

[0032] Figure 2 shows a screw 35 in three different screwing states during the screwing process with which the screw 35 is screwed into a processing object 34, for example a workpiece or a wall.

[0033] Figure 3 shows a diagram with a torque signal 43, a current signal 44 and a rotational speed signal 45. The torque signal 43 is a time profile of a torque during the screwing-in process. The torque is, for example, the torque acting on the tool 2. The current signal 44 is a time profile of an electrical current during the screwing-in process. The electrical current is, for example, the electrical current that is supplied to the drive unit 1. For example, the electrical current is a motor current of the electric motor of the drive unit 1. The rotational speed signal 45 is a time profile of a rotational speed, in particular a rotational speed of the tool 2. The torque, the electrical current and the rotational speed are respective examples of a drive variable that is related to the rotary drive of the tool 2.

[0034] The screwing process comprises, as work process phases, an acceleration phase 45, a thread screwing phase 46 and / or a screw head screwing phase 47.

[0035] During the acceleration phase 45, the rotational speed is accelerated (in particular starting from zero) to a working rotational speed 48. Advantageously, the screw 35 is screwed into the machining object 43 with a portion of its thread 36 during the acceleration phase 45.

[0036] The thread screwing-in phase 46 follows the acceleration phase 45. During the thread screwing-in phase 46, the screw is screwed with its thread 36 into the object 34 to be machined. During the thread screwing-in phase 46, the rotational speed of the tool 2 is equal to the working rotational speed 48, in particular (essentially) constant, in particular within the scope of a control accuracy of a control carried out by the power tool device 10, in particular a rotational speed control. Expediently, during the thread screwing-in phase 46, the torque and / or the electric current is (essentially) constant, in particular within the scope of a control accuracy of a control carried out by the power tool device 10.In Figure 2, the screw 35 is shown on the left in a first screw-in state, which occurs during the thread screw-in phase 46 and in which the screw 35 is already screwed into the processing object 34 with part of its thread and the screw head 39 is not yet in contact with the processing object 34.

[0037] The screw head screwing-in phase 47 follows the thread screwing-in phase 46. In the screw head screwing-in phase 47, the screw head 39 is driven into the machining object 34. In the screw head screwing-in phase 47, the rotational speed decreases and / or the torque and / or the electric current increases. In Figure 2, the screw 35 is shown in the middle in a second screwing-in state, which occurs during the screw head screwing-in phase 47 and in which the screw 35 has already penetrated the machining object 34 with part of its screw head.

[0038] Furthermore, in Figure 2, the screw on the right is shown in a third screwing-in state, which occurs after the end of the screw head screwing-in phase 47 and in which the screw head 39 with its upper side 38 is flush with the surface 41 of the processing object 34.

[0039] By way of example, the assistance procedure serves to detect the screw head screwing-in phase 47 and, in response to the detection of the screw head screwing-in phase 47, to change the rotary drive of the tool 2, for example in such a way that it is easier for a user to achieve the third screwing-in state.

[0040] The power tool device 10, in particular the control unit 19, is expediently designed, as part of the assistance procedure, to repeatedly detect a drive variable associated with the rotary drive of the tool 2 (in particular during a work process) in order to obtain drive variable values ​​that represent a temporal progression of the drive variable. The drive variable preferably comprises the rotational speed, the torque, and / or an electrical drive variable, for example the electrical current, of the drive unit 1.

[0041] The power tool device 10 is designed to calculate a cumulative sum based on deviation values ​​between the drive variable values ​​and a reference variable. The power tool device 10 preferably calculates the cumulative sum as the cumulative sum of the deviation values. The power tool device 10 preferably calculates the deviation values ​​as the difference between the drive variable values ​​and the reference variable. The calculations of the power tool device 10 are expediently carried out by the control unit 19. The power tool device 10 is in particular designed to calculate the cumulative sum according to a CUSUM method. CUSUM stands for "cumulative sum".

[0042] For example, the power tool device 10 calculates the cumulative sum according to the following formulas as S n

[0043] S o = 0 S n = max(O,S n-1 + x n — a>n ) x n is the respective drive size value and <w n is the reference value. The index n is used to refer to the drive variable values. For each drive variable value, a corresponding calculation of S is carried out successively. n For example, the cumulative sum is initially set to zero (especially at the beginning of the assistance procedure). Then, as part of the assistance procedure, for each drive variable value x n a respective deviation value x n — a> n calculated and this deviation value is added to the cumulative sum S calculated immediately before n _^ is added. The thus calculated sum value + x n — a> n is then compared with zero (exemplarily using a max function). If the sum value is greater than zero, the cumulative sum S nset to this sum value. If the sum value is less than or equal to zero, the cumulative sum S n set to zero .

[0044] Preferably, the reference value a> is based n on an average value related to the drive size and a noise parameter k . For example, the reference quantity a> n a sum of the mean value related to the drive variable and the noise parameter k . The mean value For example, during the assistance procedure, the drive size values ​​x n calculated, for example, based on "Welf ord' s online algorithm". Furthermore, for the mean A fixed value, for example a value stored in the power tool device 10, may be used. The noise parameter k can expediently be set by a user via the operating device 18, in particular the second operating element 22. Furthermore, a fixed value, in particular a value stored in the power tool device 10, may be used for the noise parameter k.

[0045] Optionally, the respective drive size value x n , the reference size <w n , the mean f n , the noise parameter k , the respective deviation value and / or the cumulative sum S n standardized, for example, to a standard deviation s . The standard deviation s is calculated, for example, during the assistance procedure based on the previously recorded drive variable values ​​x ncalculated, for example on the basis of "Welf ord's online algorithm". Furthermore, a fixed value, for example a value stored in the power tool device 10, can be used for the standard deviation s.

[0046] For example, the cumulative sum S n calculated according to the following formulas:

[0047] S o = 0

[0048] Furthermore, the cumulative sum S n can also be calculated according to the following formulas:

[0049] S o = 0

[0050] The power tool device 10 is configured to perform a drive change action based on the accumulated sum to change the rotational drive of the tool 2. The mode of the power tool device 10 assumed by the drive change action shall also be referred to as an assist mode.

[0051] Preferably, the power tool device 10 compares the cumulative sum S n (in particular any calculated cumulative sum S n ) with a limit and results in response to the fact that the cumulative sum S n reaches or exceeds the limit value, the drive change action is carried out. Conveniently, the power tool device 10 takes the action based on the cumulative sum, in particular in response to the cumulative sum S n reaches or exceeds the limit value, the assistance mode is activated. The limit value is expediently stored in the power tool device 10 and / or adjustable via the operating device 18 and / or is calculated by the power tool device 10, for example as a multiple of the mean value.

[0052] Preferably, the power tool device resets the mean and / or standard deviation in response to the cumulative sum reaching or exceeding the limit.

[0053] Preferably, at least one user parameter for the assistance procedure can be set via the operating device 18. The at least one user parameter includes, in particular, the noise parameter k for calculating the cumulative sum and / or the limit value on the basis of which the power tool device performs the drive change action.

[0054] Optionally, the power tool device is designed to repeatedly record, as part of the assistance procedure, several drive variables associated with the rotary drive of the tool 2 (for example the torque, the rotational speed and / or the electric current) in order to obtain respective drive variable values ​​for each of the drive variables, which represent a respective temporal profile of the respective drive variable. The power tool device 10 is in particular designed to calculate a respective cumulative sum for each of the drive variables on the basis of respective deviation values ​​between the respective drive variable values ​​and a respective reference variable, and to carry out a drive change action on the basis of the calculated cumulative sums in order to change the rotary drive of the tool 2.The calculation of the respective cumulative sums is expediently carried out in accordance with the above explanations (related to the calculation of a cumulative sum). Preferably, the power tool device 10 compares each of the cumulative sums with a respective limit value and executes the drive change action in response to one, several, or all of the cumulative sums reaching or exceeding their respective limit value.

[0055] The drive change action preferably comprises a reduction in the rotary drive of the tool 2, a termination of the rotary drive of the tool, an interruption of the rotary drive of the tool and / or a change of the rotary drive of the tool 2 to pulsed operation. The reduction in the rotary drive comprises, for example, a reduction in the rotational speed of the tool 2 and / or a reduction in the torque of the tool 2. During pulsed operation, for example, time-spaced torque pulses are applied to the tool 2 (by means of the drive unit 1). Between the torque pulses, the torque acting on the tool 2 can be reduced to zero. The drive change action is carried out in particular in that the control unit 19 changes the control of the drive unit 1.

[0056] The drive change action preferably comprises a reduction of a maximum rotational speed value for the rotary drive. The maximum rotational speed value defines, for example, the maximum adjustable rotational speed of the tool 2 (for example by actuating the first actuating element 21). Optionally, before the drive change action, the power tool device 10 carries out a rotational speed control of the tool 2 to a particularly fixed rotational speed setpoint value, which exemplarily represents the maximum rotational speed value (before the drive change action), and the reduced rotational speed value (after the drive change action) is particularly reduced compared to this rotational speed setpoint value.

[0057] The power tool device 10 is expediently designed to interrupt the rotary drive for a defined interruption period (particularly for reducing the maximum rotational speed value) and, following the interruption, to accelerate the rotary drive of the tool 2 until the reduced maximum rotational speed value is reached. In this way, the power tool device can make the drive change action clearly perceptible to the user.

[0058] The power tool device 10 is preferably designed to increase the maximum rotational speed value in response to a current associated with the rotary drive of the tool 2 reaching or exceeding a current threshold value after the reduction of the maximum rotational speed value carried out as part of the drive change action. The current is expediently the motor current of the electric motor. The current threshold value is expediently stored in the power tool device 10, in particular the control unit 19, and expediently describes the maximum electrical current that can be made available to the drive unit 1. After the drive change action has been carried out and the maximum rotational speed value has been reduced therewith, it may happen that there is not enough power and / or torque available for the work process to be carried out.This is particularly evident for the power tool device 10 when the current reaches the current threshold. Increasing the maximum rotational speed value (compared to the previously reduced maximum rotational speed value) makes it possible to increase the rotational speed of the tool 2 and thus the power and / or torque provided.

[0059] As mentioned above, the drive variable is, for example, the rotational speed of the tool 2, the torque acting on the tool 2 or the electric current of the drive unit 1. The power tool device 10 preferably comprises a sensor device 11 (preferably arranged at the point of action of the torque, in particular on a shaft 9) for detecting the torque, which can be used as a drive variable. The sensor device 11 comprises, for example, a strain gauge, a sensor for measuring mechanical stresses, a magnetostriction unit and / or a piezo sensor unit for detecting a mechanical deformation. The sensor device 11 is designed to detect the torque on the shaft 9, in particular a drive shaft, an output shaft and / or a motor shaft. Furthermore, the sensor device 11 can be part of the attachment 7 explained below.

[0060] The power tool device 10 preferably has the first operating element 21, which is designed, for example, as a trigger button and can expediently be positioned by user operation along an operating path 49 (for example, relative to the outer housing 12) in order to adjust the rotary drive of the tool 2 according to the position of the operating element 21 along the operating path 49. The operating path 49 is indicated in Figure 1 by a double arrow. For example, the operating element 21 can be positioned by a user along the operating path from a first end position to a second end position in order to variably adjust the rotary drive of the tool 2, in particular the rotational speed and / or the torque of the tool 2, in particular in such a way that the rotary drive, in particular the rotational speed and / or the torque, increases in the direction towards the second end position.By positioning the operating element 21 in the first end position, for example, a rotary drive, in particular a torque and / or a rotational speed, is set to zero. The first end position can expediently also be referred to as the off position. By positioning the operating element 21 in the second end position, for example, a maximum rotary drive, in particular a maximum torque and / or a maximum rotational speed (for example, according to the maximum rotational speed value) is set.

[0061] The power tool device 10 is expediently designed to carry out the assistance procedure and / or to enable the drive change action to be carried out on the basis of the cumulative sum in response to the operating element 21 reaching or exceeding a predetermined position along the operating path (in particular in the direction of the second end position). The predetermined position is preferably spaced from the first end position and / or spaced from the second end position, for example the predetermined position is located at least 50% or at least 70% and / or a maximum of 90% of the operating path in the direction of the second end position. Expediently, the assistance procedure is triggered in response to the positioning of the operating element 21 at the predetermined position, in particular immediately thereafter or with a time delay.Alternatively, the assistance procedure is started beforehand, for example by actuating the control element 21 and by positioning the control element 21 at the predetermined position, the execution of the drive change action is then released.

[0062] The power tool device 10 is in particular designed to enter an automatic mode in response to the operating element reaching or exceeding the predetermined position. The power tool device 10 is expediently designed to deactivate the possibility of manual variable adjustment of the rotary drive in automatic mode by positioning the operating element along the operating path and / or to only enable the rotary drive to be switched off by positioning the operating element along the operating path. Expediently, the power tool device 10 has a manual mode in which manual variable adjustment of the rotary drive, in particular of the rotational speed and / or the torque of the tool 2, is possible by positioning the operating element along the operating path.A manual variable adjustment of the rotary drive means in particular that the rotary drive (in particular the rotational speed and / or the torque) can be adjusted continuously and / or step by step to a plurality of different values, in accordance with, in particular proportional to, the positioning of the operating element along the operating path. In automatic mode, this option of manual variable adjustment is expediently deactivated. For example, in automatic mode the power tool device 10 sets the rotary drive, in particular the rotational speed and / or the torque, to a fixed value. For example, in automatic mode the power tool device 10 carries out a rotational speed control of the rotational speed of the tool 2 to a constant (in particular fixedly predetermined) rotational speed setpoint.Conveniently, the user can switch off the rotary drive in automatic mode, in particular by positioning the first control element 21 in the off position.

[0063] The power tool device 10 is preferably designed to switch from the automatic mode to an assistance mode based on the cumulative sum and to end the deactivation of the manual variable setting option in the assistance mode. The power tool device 10 preferably switches from the automatic mode to the assistance mode in response to the cumulative sum exceeding the limit value. The assistance mode is to be referred to in particular as the mode which prevails after the drive change action has been carried out, that is to say in particular a mode in which the rotary drive is changed, for example by reducing the maximum rotational speed value.In support mode, the user can again manually adjust the tool's rotational speed by positioning the first control element 21 along the operating path 49—in particular, up to the maximum rotational speed value. The user can thus screw the screw 35 further into the machining object 34 at a freely selectable low rotational speed until the screw head 39 is driven into the machining object 34 to a desired depth.

[0064] Preferably, the power tool device 10 is configured to reset the accumulated sum and / or terminate the assistance procedure in response to the operating element being placed in an off position.

[0065] The power tool device 10 is preferably designed to delay the start of the assistance procedure until the acceleration phase 45 of the rotary drive has ended. For example, a predetermined time period is defined in the power tool device 10, which the power tool device 10 waits from the start of the rotary drive and / or from the positioning of the first operating element 21 at the predetermined position before the power tool device 10 begins the assistance procedure, in particular before the power tool device 10 calculates the cumulative sum. In this way, it can be avoided that a drive variable changing in the acceleration phase due to the acceleration of the tool 2 affects the cumulative sum and leads to the drive change action being carried out too early or too late.

[0066] Preferably, the power tool device 10 is designed to drive the tool according to a constant rotational speed setpoint during the assistance procedure during the detection of the drive variable until the execution of the drive change action, in particular to carry out a rotational speed control of the rotational speed of the tool 2 according to the constant rotational speed setpoint. In this way, it can be achieved that the rotational speed - and thus expediently the drive variable - changes only slightly or not at all (in particular in the thread screwing-in phase), so that a change in the drive variable caused by the screw head screwing-in phase then becomes clearly apparent and can be reliably detected.

[0067] Figure 4 shows an exemplary configuration of the power tool device 10, in which the power tool device 10 comprises an attachment 7. The attachment 7 is removably attached to the drive device 6, for example to its shaft section 15. The attachment 7 is communicatively connected to the drive device 6. The attachment 7 can be designed, for example, as an additional handle. The attachment 7 is expediently not required to provide the rotary drive of the tool 2 by means of the drive unit 1. The attachment 7 is preferably used to enable the assistance procedure, to record the drive variable, to calculate the cumulative sum and / or to check whether the drive change action is to be carried out, in particular whether the cumulative sum reaches or exceeds the limit value.The attachment 7 preferably comprises an attachment sensor unit for detecting the drive variable and / or an attachment control unit. The attachment control unit is expediently communicatively connected to the control unit 19, in particular wirelessly, for example via Bluetooth, and / or wired. The attachment 7 can also be part of the operating device 18, in particular providing the second operating element.

[0068] Figure 5 shows an exemplary configuration of the power tool device 10, in which the power tool device 10 comprises a mobile device 8, for example a smartphone, which is communicatively connected to the drive device 6, in particular the control unit 19, in particular wired and / or wirelessly, for example via Bluetooth. The mobile device 8 is present separately from the drive device 6. The mobile device 8 preferably serves to activate the assistance procedure. The mobile device control unit is expediently communicatively connected to the control unit 19, in particular wirelessly and / or wired. The mobile device 8 can also be part of the operating device 18, in particular provide the second operating element. By way of example, the mobile device 8 comprises a touchscreen 42, which forms part of the operating device 18 and / or represents, for example, the second operating element.

[0069] Figure 6 shows a flowchart of a method for operating the power tool device 10. The method comprises a first step S1, in which the rotary drive of the tool 2 is started. For example, in the first step, the user actuates the operating device 18, in particular the first operating element 21, in order to cause the drive unit 1 to begin providing the rotary drive of the tool 2. By way of example, the tool 2 is at this time in engagement with a screw head of a screw to be screwed into a processing object.

[0070] The method comprises an optional second step S2, in which the user triggers execution of the assistance procedure by reaching or exceeding the predetermined position along the operating path with the first operating element 21, for example, by moving the first operating element 21 to the second end position. Alternatively, the assistance procedure can also be triggered in another way, for example, automatically.

[0071] The method includes an optional third step S3, in which the power tool device 10 delays the actual start of the assistance procedure until the acceleration phase 46 of the rotary drive is completed. For example, the power tool device 10 waits a predetermined period of time from the start of the rotary drive and / or from the positioning of the first operating element 21 in the predetermined position before the power tool device 10 begins the assistance procedure.

[0072] The method continues with the fourth step S4, in which the power tool device 10 carries out the assistance procedure (in particular in the thread screwing phase) and, as part of the assistance procedure during the rotary drive of the tool 2, repeatedly detects the drive variable associated with the rotary drive of the tool in order to obtain drive variable values ​​that represent a temporal progression of the drive variable, and calculates the cumulative sum on the basis of the deviation values ​​between the drive variable values ​​and the reference variable.

[0073] Optionally, in the fourth step S4—i.e., within the scope of the assistance procedure—the power tool device 10 enters automatic mode and, in automatic mode, regulates the rotational speed of the tool 2 to a constant rotational speed target value and / or blocks the possibility of manually variable adjustment of the rotational speed via the positioning of the first operating element 21. Optionally, the user causes the first operating element 21 to be moved to the first end position (for example, by the user removing their finger from the first operating element 21). In this case, the method continues with the seventh step S7.

[0074] The method continues with the fifth step S5 (particularly in the case where the user leaves the first operating element 21 in a position different from the first end position and / or does not remove their finger from the first operating element 21). In the fifth step S5, the power tool device 10 performs the drive change action based on the accumulated sum to change the rotational drive of the tool 2 (particularly in the screw head screwing-in phase).In particular, in response to the cumulative sum reaching or exceeding the limit value, the power tool device 10 changes from the automatic mode to the support mode, in which the maximum rotational speed value of the tool 2 is expediently reduced (in particular compared to the automatic mode) and / or the possibility of manually variable adjustment of the rotational speed via the positioning of the first control element 21 (in particular up to the reduced maximum rotational speed value) is enabled again.

[0075] The method continues with the optional sixth step in which the power tool device 10 is in the support mode and the user, by actuating the first operating element 21, causes the screw with the screw head to be screwed further into the processing object, in particular until the user causes the first operating element 21 to be moved to the first end position (for example by the user removing his finger from the first operating element 21).

[0076] In response to the first operating element 21 being moved into the first end position (for example in step S4 or in step S6), the method continues with step S7, in which the power tool device 10 stops the rotary drive of the tool and expediently ends the assistance procedure and thus in particular also the support mode.

Claims

Claims 1. Power tool device (10), in particular a screwing and / or drilling device, comprising a drive unit (1) for rotary driving a tool (2), in particular a drill or a screwdriver blade, wherein the power tool device (10) is designed to carry out an assistance procedure and, as part of the assistance procedure, to repeatedly record a drive variable associated with the rotary drive of the tool during the rotary drive of the tool (2) in order to obtain drive variable values that represent a temporal profile of the drive variable, to calculate a cumulative sum based on deviation values between the drive variable values and a reference variable, and to carry out a drive change action on the basis of the cumulative sum in order to change the rotary drive of the tool (2).

2. Power tool device according to claim 1, wherein the drive variable comprises a rotational speed, a torque and / or an electrical drive variable, for example an electrical current, of the drive unit (1).

3. Power tool device (10) according to any preceding claim, wherein the drive change action comprises a reduction of the rotary drive of the tool (2), a termination of the rotary drive of the tool (2), an interruption of the rotary drive of the tool (2) and / or a change of the Rotary drive of the tool (2) to a pulsed operation.

4. Power tool device (10) according to one of the preceding claims, wherein the drive changing action comprises a reduction of a maximum rotational speed value for the rotary drive, wherein the power tool device (10) is expediently designed to interrupt the rotary drive for a defined interruption period and, following the interruption, to accelerate the rotary drive of the tool (2) until the reduced maximum rotational speed value is reached.

5. Power tool device (10) according to claim 4, wherein the power tool device (10) is designed to increase the maximum rotational speed value in response to a current associated with the rotary drive of the tool (2) exceeding a current threshold value after the reduction of the maximum rotational speed value carried out as part of the drive change action.

6. Power tool device (10) according to one of the preceding claims, wherein the reference variable is based on a mean value related to the drive variable and a noise parameter.

7. Power tool device (10) according to one of the preceding claims, comprising an operating device (18) via which at least one user parameter for the assistance procedure can be set, wherein the at least one user parameter is / is a noise parameter for calculating the cumulative sum and / or a limit value, on the basis of which the power tool device carries out the drive change action.

8. Power tool device (10) according to any preceding claim, wherein the power tool device (10) has a first operating element (21), in particular a trigger button, which can be positioned along an operating path (49) by a user operation in order to adjust the rotary drive of the tool (2) according to the position of the operating element (12) along the operating path (49), wherein the power tool device (10) is designed, in response to the first operating element (21) reaching or exceeding a predetermined position along the operating path (49), to carry out the assistance procedure and / or to enable the execution of the drive change action on the basis of the cumulative sum.

9. Power tool device according to claim 8, wherein the power tool device (10) is designed to enter an automatic mode in response to the first operating element (21) reaching or exceeding the predetermined position and, in the automatic mode, to deactivate a possibility of manual variable adjustment of the rotary drive via the positioning of the operating element (21) along the operating path (49) and / or to only enable the rotary drive to be switched off via the positioning of the operating element (21) along the operating path.

10. The power tool device (10) according to claim 9, wherein the power tool device (10) is configured to switch from the automatic mode to an assist mode based on the cumulative sum and to terminate the deactivation of the manual variable setting option in the assist mode.

11. Power tool device (10) according to one of claims 8 to 10, wherein the power tool device (10) is configured to reset the accumulated sum and / or terminate the assistance procedure in response to the first operating element (21) being placed in an off position.

12. Power tool device (10) according to any preceding claim, wherein the power tool device (10) is designed to delay a start of the assistance procedure until an acceleration phase of the rotary drive is completed.

13. Power tool device (10) according to any preceding claim, wherein the power tool device (10) is configured to drive the tool on the basis of a constant rotational speed setpoint during the detection of the drive variable until the execution of the drive change action in the assistance procedure.

14. Power tool device (10) according to any preceding claim, comprising a drive device (6) which comprises the drive unit (1), and an attachment (7) removably attached to the drive device (6) for enabling the assistance procedure, detecting the drive variable (AG), calculating the cumulative sum and / or checking whether the drive change action is to be carried out.

15. Method for operating a power tool device (10), in particular a screwing and / or drilling device, with a drive unit (1) for rotating a tool (2), in particular a drill or a screwdriver blade, comprising the steps: - Starting (S1) the rotary drive of the tool (2), - Carrying out an assistance procedure, and, within the scope of the assistance procedure: during the rotary drive of the tool (2), repeatedly recording a drive variable (AG) associated with the rotary drive of the tool in order to obtain drive variable values which represent a temporal progression of the drive variable, - Calculating a cumulative sum based on deviation values between the drive variable values and a reference variable, and - based on the cumulative sum, performing a drive change action to change the rotation drive of the tool ( 2 ).

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