METHOD FOR CONTROLLING OR REGULATING A HAND-HELD POWER TOOL

Abstract

A method for controlling or regulating a hand-held power tool, in particular a screwdriver, preferably a rotary impact screwdriver. The method includes: application of a first torque, in particular torque impulse, to a screw in a first direction of rotation, and application of a second torque, in particular torque impulse, to the screw, in a second direction of rotation opposite to the first direction of rotation.

Claims

1-16. (canceled)

17. A method for controlling or regulating a hand-held power tool, the method comprising the following steps: applying a first torque to a screw in a first direction of rotation; and applying a second torque to the screw in a second direction of rotation opposite to the first direction of rotation.

18. The method as recited in claim 17, wherein the hand-held power tool is a rotary impact screwdriver.

19. The method as recited in claim 17, wherein the applying of the first torque includes applying one or a plurality of first torque impulses to the screw in the first direction of rotation.

20. The method as recited in claim 17, wherein the applying of the second torque includes applying one or a plurality of second torque impulses to the screw in the second direction of rotation.

21. The method as recited in claim 19, wherein a number of the first torque impulses in the first direction of rotation can be set.

22. The method as recited in claim 19, wherein a number of the second torque impulses in the second direction of rotation can be set.

23. The method as recited in claim 17, wherein the application of the second torque to the screw in the second direction of rotation takes place as a function of an actuation or a deactivation of an actuating element for controlling or regulating a drive unit of the hand-held power tool.

24. The method as recited in claim 17, wherein the application of the second torque to the screw in the second direction of rotation takes place as a function of an activation of a rotary impact function of the hand-held power tool.

25. The method as recited in claim 17, wherein a first target torque is provided for limiting an application of the first torque to the screw in the first direction of rotation.

26. The method as recited in claim 25, wherein the application of the second torque to the screw in the second direction of rotation is a function of a reaching of the first target torque in the first direction of rotation.

27. The method as recited in claim 17, wherein the application of the second torque to the screw in the second direction of rotation is capable of being activated or deactivated via a switching button or an external device.

28. The method as recited in claim 17, wherein a second target torque is provided for limiting an application of the second torque to the screw in the second direction of rotation.

29. The method as recited in claim 17, wherein a time duration of the second torque acting on the screw in the second direction of rotation is provided.

30. The method as recited in claim 17, wherein the second torque is smaller in relation to the first torque.

31. The method as recited in claim 17, wherein the second target torque is smaller relative to the first target torque by up to 95%.

32. The method as recited in claim 17, wherein the second target torque is smaller relative to the first target torque by up to 40%.

33. The method as recited in claim 17, wherein the second target torque is smaller relative to the first target torque by up to 30%.

34. The method as recited in claim 17, wherein the second target torque is smaller relative to the first target torque by 10%.

35. The method as recited in claim 17, wherein a rotational movement in the second direction of rotation has an angle of rotation of up to 20°.

36. The method as recited in claim 17, wherein a rotational movement in the second direction of rotation has an angle of rotation of up to 15°.

37. The method as recited in claim 17, wherein a rotational movement in the second direction of rotation has an angle of rotation of up to 10°.

38. The method as recited in claim 17, wherein a rotational movement in the second direction of rotation has an angle of rotation of up to 8°.

39. The method as recited in claim 17, wherein a rotational movement in the second direction of rotation has an angle of rotation of up to 5°.

40. A hand-held power tool configured to: apply a first torque to a screw in a first direction of rotation; and apply a second torque to the screw in a second direction of rotation opposite to the first direction of rotation.

41. The hand-held power tool as recited in claim 40, further comprising: a communication unit configured to receive data from an external device and to set data of the hand-held power tool.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Further advantages result from the description below of the figures. The figures show exemplary embodiments of the present invention. The figures and the description contain numerous features in combination. The person skilled in the art will also usefully regard the features individually and combine them to form appropriate further combinations, in view of the disclosure herein.

[0038] FIG. 1 shows a perspective view of a hand-held power tool.

[0039] FIG. 2 shows a cross-section of a torque-transmitting region and of the screw means.

[0040] FIG. 3 shows a flow diagram of a method according to an example embodiment of the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0041] In the Figures, identical components are provided with the same reference characters.

[0042] The Figures each relate to a hand-held power tool 101 having a receptacle unit 103 for accepting tool attachments (not shown), such as a screwdriver bit, fashioned as a hexagonal nut, for screwing screws into a workpiece. Receptacle unit 103 has a conventional clamping device 105 that is provided in order to hold the tool attachment in or on hand-held power tool 101.

[0043] Hand-held power tool 101 is in particular a battery-operated screwdriver, in particular a battery-operated drill screwdriver or a battery-operator rotary impact screwdriver.

[0044] FIG. 1 shows hand-held power tool 101 having a drive unit 13, in particular a drive shaft (not shown) for transmitting a movement to a driven unit 14, in particular a driven shaft (not shown) of driven unit 14. Drive unit 13 is provided in particular to transmit a movement of drive unit 13 to a tool attachment (not shown). Drive unit 13 has an electric motor 13 realized as an electronically commutated direct-current motor. Driven unit 14 includes receptacle unit 103 and clamping device 105.

[0045] Hand-held power tool 101 has a machine housing realized at least partly as a handle casing 15 that forms an external housing 17 of hand-held power tool 101. Handle casing 15 is provided in order to be grasped by a hand of an operator of hand-held power tool 101.

[0046] In addition, hand-held power tool 101 has an interface unit 19 having a holding unit 21 that can be detachably fastened to a battery unit 23. Holding unit 21 is provided to hold battery unit 23 in a fastened state, connected to hand-held power tool 101. In addition, machine housing 15 has an actuating element 25 for switching on an off and on/off switch 25 on drive unit 13, and has a gearing unit (not shown) preferably realized as a planetary gearing. The gearing unit includes at least two gears switchable by a switching button 29.

[0047] In addition, hand-held power tool 101 has a rotary impact mechanism (not shown in more detail) that is provided to apply rotary impact impulses to the screw means (i.e., the screw) in order to screw in the screw means.

[0048] Machine housing 15 further includes a holding unit 21 that at least in some segments forms an external housing 17. Machine housing 15 is substantially made of plastic. Machine housing 15 is made with a shell construction. Holding unit 21 bounds hand-held power tool 101 from a side of the handle casing oriented away from drive unit 13. Holding unit 21 is made of metal. Holding unit 21 is fashioned as a holding clip 21.

[0049] In a fastened state, battery unit 23 is connected with hand-held power tool 101, so that there is an electrical contact of battery unit 23 with drive unit 13 of hand-held power tool 101 when battery unit 23 is connected to interface unit 19. Battery unit 23 supplies hand-held power tool 101 with electrical energy. At least battery pack 23, drive unit 13, on/off switch 25, and electronics unit 37 are electrically connected by lines 43.

[0050] Hand-held power tool 101 additionally has a mechanical coupling unit 115 for coupling the driveshaft of drive unit 13 to the driven shaft of driven unit 14. Coupling unit 115 has at least one slip clutch. Coupling unit 115 can be coupled to the gearing unit. Coupling unit 115 can be realized as an adjustable torque coupling by which a torque can be manually set. For example, a maximum torque of 100 Nm or 200 Nm or 1000 Nm can be set in order to encompass a preferred torque range from 0.1 to 20 Nm, so that in particular coupling unit 115 is set into a clutch slipping state when this torque is exceeded.

[0051] Hand-held power tool 101 has an electronics unit 37 that is set up to regulate drive unit 13.

[0052] Electronics unit 37 can acquire the torque directly via an acceleration sensor provided for this purpose, and/or indirectly, for example via a measurement of the current strength of drive unit 13, which behaves substantially proportionally to the torque of drive unit 13. Electronics unit 37 has a computing unit, such as a microcontroller, for reading out and/or processing the torque and the direction of rotation.

[0053] Hand-held power tool 101 is provided to carry out a method for controlling or regulating a hand-held power tool 101, in particular a screwdriver, including at least the steps described in the following (FIG. 3).

[0054] In a step 201, the method is started, and in a further step 203 it is optionally checked whether a rotary impact function is activated, so that in the case of an activated rotary impact function step 205 is carried out, and in the case of a deactivated rotary impact function step 207b is carried out.

[0055] If the rotary impact function is not activated, then in step 205 the rotary impact function is activated. For example, given the use of a rotary impact screwdriver the rotary impact function may not be capable of being deactivated, so that steps 203 and 205 are then omitted.

[0056] In a further step 207a, a first torque, in particular torque impulse, is applied to screw means (i.e., screw) 129 in a first direction of rotation. Here screw means 129 is to be tightened preferably up to a first target torque, or assembly torque. As a function of a state of actuation of the actuating element, such as an activated or a deactivated actuating element, or a functional state of the hand-held power tool, such as kickback activation, reaching a target torque, e-clutch, etc., a skip to step 209 can take place.

[0057] In order to screw in a screw means 129, the first torque is applied to screw means 129 in the first direction of rotation in order to tighten the screw for example to a desired depth or a desired torque.

[0058] Torque-transmitting region 131 is realized as a screw nut that is capable of being coupled to a driven unit of the hand-held power tool. The screw nut has an inner hexagonal cross-section, and the screw head has an outer hexagonal cross-section. Of course, a Torx bit and a Torx screw, hexagonal bit, and internal hexagonal screw can also be used.

[0059] In a further step 209, a direction of rotation of the drive unit is reversed, and in step 211 a second torque, in particular torque impulse, in a second direction of rotation that is opposite the first direction of rotation is applied to screw means 129.

[0060] The release of the jamming should take place here while avoiding a reduction in the first target torque, or of the assembly torque of screw means 129 in the first direction of rotation, so that it is ensured that the screw means does not detach.

[0061] The first direction of rotation is in the clockwise direction. The second direction of rotation is in the counterclockwise direction. The first direction of rotation and the second direction of rotation run opposite to one another.

[0062] The application of the first torque and/or of the second torque to screw means 129 can take place at least partly through a first torque impulse and/or a second torque impulse. Of course, there may be a plurality of torque impulses.

[0063] A number of torque impulses in the first and/or second direction of rotation can be set, so that the number of torque impulses that are to be applied to screw means 129 can be set.

[0064] The application of the second torque, in particular torque impulse, in the second direction of rotation to screw means 129 can take place as a function of an actuation, in particular an activation or a deactivation, of an actuating element 25 for controlling or regulating a drive unit of hand-held power tool 101. In particular, actuating element 25 is provided to control or to regulate the drive unit so that a compressed actuating element 25 is provided in order to tighten or screw in screw means 129.

[0065] The application of the second torque, in particular torque impulse, in the second direction of rotation to screw means 129 takes place as a function of an activation of a rotary impact function of hand-held power tool 101, because, in particular given the use of a rotary impact function, there is a high risk of jamming, so that hand-held power tool 101 preferably applies the second torque, in the second direction of rotation, to screw means 129 after each actuation, or screwing process, of hand-held power tool 101.

[0066] The rotary impact function can be set in step 203 so that when the rotary impact function is activated steps 205 through 215 are carried out.

[0067] For the ideal screwing in of screw means 129, the first target torque can be adjusted, so that the first target torque is provided in order to limit an application of the first torque, in particular torque impulse, to screw means 129 in the first direction of rotation. The first torque and/or the first target torque can be acquired electronically, for example via at least one sensor unit of hand-held power tool 101. For example, the torque could be measured via a drive current strength with which the drive unit is operated.

[0068] The method can include an application of the second torque, in particular torque impulse, to screw means 129 in the second direction of rotation as a function of, in particular, a reaching of the first target torque in the first direction of rotation. Here, a torque in a second direction of rotation can be applied to screw means 129 if, or after, screw means 129, with the first torque in the first direction of rotation, has reached or exceeded the first target torque, so that the direction of rotation is reversed after reaching or exceeding the first target torque.

[0069] The second torque, in particular torque impulse, in the second direction of rotation can be capable of being activated or deactivated by a switching button or an external device 119.

[0070] In addition, the method can regulate a provision of a time duration of the second torque, in particular torque impulse, acting on screw means 129 in the second direction of rotation, so that the drive unit is switched off if the second torque, in the second direction of rotation, is applied to screw means 129 with a time duration of up to 5 s.

[0071] The method can include a provision of a second target torque for limiting an application of the second torque, in particular torque impulse, to screw means 129 in the second direction of rotation. The second target torque can be adjustable in particular as a function of the first torque in the first direction of rotation. The first target torque should be, in the first direction of rotation, smaller than the second target torque in the second direction. Here the second target torque, in particular torque impulse, is smaller relative to the first target torque, in particular torque impulse, by up to 90% and by at least 70%. The second target torque, in particular torque impulse, can deviate from the first target torque, in particular torque impulse, by up to 30% and by at least 10%.

[0072] In step 213, the drive unit can have a rotational movement by an angle of rotation φ in the second direction of rotation of up to 15°. Here an angle of rotation φ can be greater than 2°.

[0073] In a further step 215, the method, or tightening process, ends.

[0074] In addition, hand-held power tool 101 has a communication unit 117 for receiving data from an external device 119 and for setting the data of hand-held power tool 101.

[0075] Communication unit 117 is provided to control or to regulate the drive unit in wireless fashion. Communication unit 117 has a first communication module that is situated on or in external device 119. Communication unit 117 has a second communication module that is situated on or in the hand-held power tool drive unit. Of course, second communication module is connected to electronics unit 37. Electronics unit 37 is provided to control or to regulate the drive unit. Electronics unit 37 is connected to the second communication module in particular electrically, or by electrical lines. Hand-held power tool 101 has at least one communication unit 117 for communication with at least one external unit, for an exchange of electronic data at least for controlling or regulating the drive unit. Communication unit 117 is preferably realized as a wireless communication unit 117. Here communication unit 117 is realized as a Bluetooth communication unit 117. Particularly preferably, electronics unit 37 is provided to control or to regulate the drive unit and/or safety functions of hand-held power tool 101 as a function of an actuation of the actuation unit and as a function of electronic data transmitted to electronics unit 37 by communication unit 117. The external unit is preferably realized as a smart phone that has an app for communication with communication unit 117. Settings stored in the external unit are thus preferably capable of being transmitted directly to hand-held power tool 101.