Reversible torque wrench

Abstract

The invention relates to a torque wrench having a drive arm (2) in which a torque-limiting device is arranged by means of which a limit torque can be set. When the limit torque applied to the drive arm (2) is overcome, a stop flank (6) strikes a stop point (7) such that a click can be perceived. By displacing a reversing switch (10), this click function can be deactivated in that the displacement path of a blocking body (9) is blocked.

Description

Description Reversible torque wrench field of technology

[0001] The invention relates to a screwdriving tool in the form of a torque wrench. The torque wrench has a driven element onto which, for example, a socket can be attached and which is mounted on a head. By rotating the driven element, a screw can be turned around an axis. A drive arm projects radially from the head with respect to the axis. When a torque is applied to the driven element that reaches a preset limit torque, a stop flank strikes a stop point in a perceptible manner, for example, audibly or by touch. State of the art

[0002] US Patent 4,655,104 A describes such a torque wrench. The drive arm is a tube with an adjusting element at its end, which alters the force exerted on a force accumulator acting on a plunger. A lever arm allows the force applied to the plunger to be transferred as torque to a transmission arm located inside the tube. The transmission arm is pivotally mounted within the tube and rigidly connected to an output element. When a limit torque is reached, a stop formed by the transmission arm strikes a stop point on the inner wall of the tube. This produces a tactile or audible click.

[0003] German patent DE 10 2018 131 903 A1 describes a torque wrench with which a torque can be applied to a driven element, wherein the driven element interacts with a head via a freewheel mechanism. Only torques can be applied with this torque wrench. 31312PCT - 14.10.2025 Torques below an adjustable limit are transmitted. A switching element can be moved from a basic position, in which only torques below the limit are transmitted, to a blocking position, in which torques above the limit can also be transmitted to the output element.

[0004] From DE 10 2008 055 581 Al a screw tool with a switchable freewheel lock is known.

[0005] US Patent 7,458,297 B1 describes an electronic torque wrench with a force sensor that measures the torque applied to a head. An electronic circuit triggers the movement of a release pin when a limit torque is reached. In its locked position, the release pin prevents a transmission arm located in a handle from pivoting. In its released position, the release pin allows the transmission arm to pivot, so that a stop flank engages a stop point within the handle.

[0006] US Patent 7458297 Bl discloses an electronic torque wrench with a working head that is pivotally connected to a housing via a shaft section. A strain sensor measures the applied torque, and as soon as a processor in the torque wrench detects that the preset torque limit has been exceeded, balls that fix the working head relative to the housing are released, causing the working head to pivot relative to the housing and strike the housing wall. Disabling this function is not provided for. 31312PCT - 14.10.2025

[0007] GN 2217486 Y pertains to a torque wrench with a ratchet head connected to a push rod via a bolt and a connecting plate. A limit torque can be preset using a spring, a slider, and an adjustment mechanism. If this limit is exceeded, the push rod is adjusted in such a way that a screw lifts off a projection, causing the ratchet head to tilt relative to the housing. A lever arm connected to the ratchet head then strikes the housing wall, generating a tactile and audible release signal. The screw serves solely for adjustment on the projection.

[0008] German patent DE 10 2018 131 903 A1 describes a screwdriving tool in which a torque transmission element is pressed into a recess of the torque transmission section by a spring force via a plunger. If the set limit torque is exceeded, inclined flanks of the recess push the transmission element radially outwards, causing it to leave the recess, overshoot a tooth, and snap into the next recess. This disengagement creates the typical "stop" sound and limits the transmissible torque. A switching mechanism allows the tool to be used either as a torque wrench or as a ratchet.

[0009] German patent DE 3933913 discloses a torque wrench in which the torque is transmitted from a wrench body to a wrench shaft via transmission balls. These balls are held in engagement by an axial ball and a coil spring. As soon as the set limit torque is exceeded, the balls are displaced against the spring force, the positive locking of a coupling is released, and the wrench shaft can continue to rotate freely relative to the wrench body. A locking element can be used to block the axial movement of the spring plate, so that the balls can no longer move and the wrench acts like a rigid wrench. 31312PCT - 14.10.2025

[0010] US 2918834 A describes a torque wrench in which an output shaft works via an arm with a roller against a spring-loaded cam. If the set limit torque is exceeded, roller 32 overcomes a cam shoulder of the cam and continues running on an inclined surface, whereby the cam is pushed back against the spring. This creates a yielding area with continued spring resistance, so that the operator feels the release. Summary of the invention

[0011] The invention is based on the objective of further developing a generic screwdriving tool in a way that is advantageous for practical use. The invention is further based on the objective of expanding the range of applications of the generic screwdriving tool.

[0012] According to a first aspect of the invention, a torque wrench of the generic type is further developed by a switching element that can be moved from a home position to a locking position. In the home position, the wrench can be used like a torque wrench of the generic type, in which a stop flank abuts a stop point when the limit torque is reached. If the switching element is moved from the home position to a locking position, the abutment is blocked. Thus, when the preset limit torque is reached and / or exceeded, the stop flank is prevented from abutting the stop point. The torque wrench can have a transmission arm that is rotationally fixed to the head, against which, as in the prior art, a counter-torque is exerted by means of a power storage device. This counter-torque is overcome when the limit torque is reached, so that the transmission arm, held in a rest position by the energy storage device, rotates around an axis of rotation about which the transmission arm rotates relative to itself. 31312PCT - 14.10.2025 The drive arm can be slightly rotated, pivoting so that the stop flank abuts the stop point in a stop position and subsequently rests against it until the torque applied to the transmission arm is reduced. In the locking position, this pivoting capability can be blocked. According to a preferred embodiment of the invention, it is proposed that the switching element forms a recess into which a locking element can immerse to reach the stop position. The recess can also be formed by a step. The locking element can be associated with an end section of the transmission arm. It can be fixed to the transmission arm. By moving the switching element from its home position to its locking position, the recess can be moved out of the path of movement of the locking element, in which the locking element moves when the transmission arm pivots.The locking element may be designed to form a stop flank that abuts the bottom of the recess when the limit torque is exceeded. The locking element may extend through a window in the drive arm. Alternatively, the stop flank may be formed by a transmission element, such as a transmission lever, which is pivotable about a pivot axis within a cavity of the drive arm. The transmission element may be actuated by an end section of the transmission arm. In this configuration, the transmission element may be actuated by the energy storage device. The stop flank may also be formed by the transmission arm itself, which abuts an inner wall of a cavity that accommodates the transmission arm.

[0013] It may be provided that a movable element is arranged within a cavity of the drive arm, the movement of which can be blocked by means of a transmission element, for example, a locking element. The movable element can, in particular, be a transmission arm connected to the head, which moves from its rest position to its stop position. 31312PCT - 14.10.2025 The drive arm can pivot when the limit torque is reached. This pivotability can be blocked by means of the locking element. For this purpose, the locking element can be moved from a home position to a locking position. The switching element can be provided that it interacts directly with the locking element. While the locking element is preferably arranged in the cavity of the drive arm, the switching element can be arranged on the outside of the drive arm. The switching element can be displaceable or rotatable relative to the drive arm. Preferably, the switching element is a slide that is displaceable in the direction of extension of the drive arm. It can be formed by a sleeve that surrounds the drive arm. The sleeve can be fixed to the drive arm so as not to rotate. However, it can also be rotated relative to the drive arm. In a preferred embodiment, the sleeve forms the recess, which can be formed by an annular groove.The annular groove preferably runs along an inner surface of the sleeve. The sleeve can lock into two positions. A first position corresponds to the home position, and a second position corresponds to the locking position. In the home position, the recess can be located at the level of a window in a wall of the drive arm, allowing the locking element to interact with the recess through the window. In the locking position, the recess can be offset relative to the window, preventing the locking element from entering the recess. In the locking position, the movement of the locking element is restricted. In the home position, an end section of the transmission arm can rest against a section of the inner wall of the drive arm's cavity.When a torque is applied, the transmission arm can detach from this section of the inner wall of the cavity and take the locking element with it, until either the transmission arm or a transmission element strikes another section of the inner wall or the locking element strikes another section of the inner wall or the switching element, in particular a sleeve formed by the switching element. 31312PCT - 14.10.2025

[0014] According to a second aspect of the invention, a freewheel lock is arranged in the head. The freewheel lock has a freewheel direction in which the output element can rotate freely relative to the head. It has a locking direction opposite to the freewheel direction, in which the output element cannot rotate relative to the head. With such a freewheel lock, the output element can be rotated stepwise in a torque transmission device by pivoting the drive arm back and forth. A switch can be provided with which the locking direction of the freewheel lock can be reversed. It can also be provided that the freewheel lock can assume a neutral position by connecting the output element to the head in a rotationally fixed manner in both directions of rotation. The freewheel lock can be designed according to DE 10 2018 131 903 A1 or according to DE 102014 113 758 A1.

[0015] The screwdriver preferably has an adjusting element with which the limit torque can be set. The adjusting element can be formed by a section of the drive arm's handle. This section of the handle can be rotatable. By rotating the handle section, a compression spring forming the energy storage device can be tensioned. This compression spring can act on a plunger, which transmits a force to a transmission element or the transmission arm via a toggle-lever extension lever. This force has a radial component extending in the direction of the drive arm's extension and an azimuthal component that exerts a torque on the transmission element or the transmission arm.The extension lever can extend when a torque is applied to the drive arm, whereby the azimuthal force component decreases until the transmission element, for example a transmission lever, abuts the drive arm or until a section of the transmission arm abuts the drive arm. According to a variant of the invention, however, a blocking element can also abut the switching element. 31312PCT - 14.10.2025 Brief description of the drawings

[0016] Exemplary embodiments of the invention are explained below with reference to the accompanying drawings. These show: Fig. 1 shows a view of a first embodiment, Fig. 2 partially broken open to show a further view rotated by 90°, Fig. 3 shows section III in Fig. 2, partially broken open, Fig. 4 enlarges a section along section line IV-IV in Fig. 1, with a transmission arm 5 in its rest position, Fig. 5 shows a representation according to Fig. 4, wherein the transmission arm 5 is pivoted into a stop position, Fig. 6 enlarges section VI in Fig. 4, Fig. 7 enlarges section VII in Fig. 5, Fig. 8 shows the section according to Figures 6 and 7, but in a blocked position; Fig. 9 shows the section according to Unit IX-IX in Fig. 7. Fig. 10 shows the section along line XX in Fig. 8, Fig. 11 shows a perspective exploded view of the essential elements of the first embodiment, 31312PCT - 14.10.2025 Fig. Ila shows another perspective exploded view of elements of a switch 10, Fig. 12 shows a second embodiment in a representation according to Fig. 1 of the first embodiment, Fig. 13 the second embodiment in a similar representation. Fig. 2 in a rest position, Fig. 14 shows detail XIV in Fig. 13, Fig. 15 shows the second embodiment in the stop position, Fig. 16 shows the second embodiment in the blocking position, Fig. 17 shows the section along line XVII-XVII in Fig. 13, Fig. 18 shows the section along line XVIII-XVIII in Fig. 15, Fig. 19 shows the section along line XIX-XIX in Fig. 16, Fig. 20 is a perspective exploded view of the second embodiment and Fig. 21 is a perspective exploded view of the elements of the Switch 10. 31312PCT - 14.10.2025 Description of the embodiments

[0017] The embodiments of the invention relate to a torque wrench having an output element 3 in the form of an output pin 3, which has a polygonal profile, in particular a square profile. The output element 3 is coupled to a drive arm 2 in a torque-transmitting manner by means of a freewheel lock 40. The drive arm 2 projects from a head 1 in which the freewheel lock 40 is arranged. A switch 4 is located on a broad side of the head 1, with which the locking direction of the freewheel lock 40 can be changed. In a right-hand screw position, the drive arm 2 can be freely rotated counterclockwise relative to the output element 3. If the drive arm 2 is rotated clockwise, the output element 3 is driven along with it. In a right-hand screw position, the drive arm can be freely rotated clockwise relative to the output element 3. When rotating counterclockwise, the output element 3 is dragged along.In a neutral position, the output element 3 can be freely rotated relative to the head 1. However, in another embodiment, a neutral position is also possible in which the output element 3 is dragged along in both directions of rotation.

[0018] The head 1 is rigidly connected to a transmission arm 5. The transmission arm 5 is slightly rotatable about a pivot axis 12 relative to the drive arm. The pivot axis 12 is located in the region of a head-side end of the drive arm 2. The drive arm 2 forms a tube. The transmission arm 5 extends into a cavity 13 of the drive arm 2 and has an end section 5' opposite the head 1. The transmission arm 5 engages the cavity 13 with a pivoting clearance, allowing the end section 5' to pivot between a section 13' of the inner wall and a section 13" of the inner wall. 31312PCT - 14.10.2025

[0019] One end of the drive arm 2 carries an adjusting element 29, which can be rotated relative to the drive arm 2 to adjust the preload of a force storage element 11, formed by a compression spring. This can be done via a thread. The force storage element 11 acts on a plunger 25, which is displaceable in the cavity 13 of the drive arm 2 and which supports a rolling element 38 at its end. A pivot pin 26' extends through this rolling element, forming a pivot point for a lever 26. The lever 26 is an extension lever that can move into an extended position during operation.

[0020] The extension lever 26 engages with a pivot pin 26" either on a transmission element 24 or directly on the end section of the transmission arm 5. When a torque is transmitted to the head 1 via the drive arm 2, the extension lever 26 is extended upon reaching a limit torque defined by the force of the energy storage device 11. This causes the drive arm 2 to move from a rest position to a stop position, in which a stop flank 6, 6' abuts a stop point 7, 7' in a perceptible manner, for example, by touch or sound. This is accompanied by a slight pivoting of the transmission arm 5.

[0021] In the embodiments of the invention, a transmission body 9 in the form of a locking element 9 is provided, which, in a basic position, enables the previously described pivoting of the transmission arm 5 to the stop position, in which the stop flank 6, 6' abuts the stop point 7, 7'. The locking element 9 interacts with a switching element 10, which, in the embodiments, is formed by a sleeve that is slidable relative to the drive arm 2. The drive arm 2 projects through the cavity of the sleeve. The locking element 9 can be positively locked to the end section 5' of the transmission arm 5. A section of the locking element 9 can be inserted into a window 14 in the wall of the 31312PCT - 14.10.2025 The cavity 13 engages. The end face of the blocking body 9, extending outwards through the window 14, can form a stop flank 6, 6'.

[0022] In the initial position, the locking body 9 engages in a recess 16 of the switching element 10. The bottom of the recess 16 can form a stop point 7, 7' against which the end face of the locking body 9 can abut.

[0023] The switching element 10 can be held in the home position by means of detent elements. In the home position, an indicator sleeve 30, which is firmly connected to a sleeve 15, for example an inner sleeve of the switching element 10, can be in a concealed position. For this purpose, the indicator sleeve 30 can be inserted into a recess 31. The recess 31 can be an annular cavity.

[0024] The switching element 10 can be moved from the home position to a locking position in the extension direction of the drive arm 2. In the locking position, the recess 16 lies outside the path of movement of the locking body 9. In the locking position, a locking point 8 lies within the path of movement of the locking body 9. The locking point 8 is closer to the transmission arm 5 in its rest position than the stop point 7, 7'. As a result, the pivoting movement of the transmission arm 5 is reduced in the locking position. In the embodiments of the invention, the pivoting movement of the transmission arm 5 is blocked in the locking position.

[0025] In the blocking position, an end section 5' of the transmission arm 5 can abut a section 13" of the inner wall of the cavity 13. 31312PCT - 14.10.2025 and simultaneously support an end face of the blocking body 9 at a blocking point 8 of a sleeve 15 of the switching element 10.

[0026] In the first embodiment shown in Figures 1 to 11, a transmission element 24 in the form of a transmission lever is provided, which is pivotably mounted in the cavity 13 of the drive arm 2 about a pivot axis 22. A pin 21, which is connected to a first arm of the two-armed transmission element 24, acts on a shoulder of the end section 5'. The opposite arm of the transmission element 24 is connected to the extension lever 26 by the pivot pin 26". This arm also carries an adjusting element 27 in the form of an adjusting screw. The wall of the cavity 13 forms a window 35 through which the head of the adjusting screw 27 is accessible to a tool. An end section of the shaft of the adjusting screw 27 can pass through windows 36, 37 on the opposite side.

[0027] In this embodiment, a longer arm of the two-armed transmission element 24 can be hammer-shaped and form the stop flank 6, which, in the stop position, engages a stop point 7 of the drive arm 2. An inner tube 28 can extend within the tubular drive arm 2, forming a window 36 through which the stop flank 6 can pass.

[0028] The switching element 10 can consist of a sleeve 15 which is connected to the indicator sleeve 30 via a positive locking element 32, for example a hook that engages in a retaining recess 33. A cuff 34 can be arranged on the sleeve 15, with which the sleeve 15 can be moved. 31312PCT - 14.10.2025

[0029] In this embodiment, the locking body 9 has a cuboid shape and forms a control chamfer 18, which can interact with an edge of the recess 16 designed as an annular groove. A shaft is attached to the locking body 9, forming a positive locking element 17 that is inserted into a bore 20 of the end section 5'.

[0030] In the second embodiment shown in Figures 12 to 21, the extension lever 26 engages directly at the end section 5' of the transmission arm 5. A pivot pin 26" passes through a bore 39 of the end section 5'.

[0031] The end section 5' has a threaded bore 20 into which a threaded positive locking element 17 engages, which is firmly connected to the locking body 9. In this embodiment, the locking body 9 is formed by the cylindrical head of a screw.

[0032] The switching element 10 has an inner sleeve 15 which is slidably guided on the drive arm 2, which is designed as a tube, as in the first embodiment. The inner sleeve 15 has a window that forms a recess 16. The stop flank 6 formed by the locking body 9 can engage in this recess 16 in the stop position until it abuts the bottom of the recess 16, which is formed by an outer sleeve 19.

[0033] In the locked position, the stop flank 6 rests against a locking point 8. The locking point 8 is formed by an inner wall of an inner sleeve 15, which is inserted into an outer sleeve 19. In this embodiment, the stop point 7 is formed by a section of the inner wall of an outer sleeve 19, and the locking point 8 is formed by an inner wall of an inner sleeve 15. 31312PCT - 14.10.2025

[0034] The foregoing statements serve to explain the inventions covered by the application as a whole, which each independently further develop the prior art at least through the following combinations of features, whereby two, several or all of these combinations of features may also be combined, namely:

[0035] A screw tool characterized in that the contact of the stop flank 6, 6' at the stop point 7, 7' can be blocked by moving a switching element 10 from a basic position to a blocking position.

[0036] A screwdriving tool characterized by a transmission arm 5 non-rotatably connected to the head 1, on which a force generated by a power storage device 11 exerts a counter-torque which is overcome when the limit torque is reached, so that the transmission arm 5, held in a rest position by the power storage device 11, pivots about a rotational axis 12 relative to the drive arm 2 until the stop flank 6, 6' abuts the stop point 7, 7' in a stop position.

[0037] A screw tool characterized in that the switching element 10 forms a recess 16 into which a locking element 9 can immerse to reach the stop position, wherein a locking point 8 is adjacent to the recess 16, against which the locking element 9 rests in the locking position.

[0038] A screw tool characterized in that the stop point 7 is formed from the bottom of the recess 16. 31312PCT - 14.10.2025

[0039] A screw tool characterized in that the stop flank 6' is formed by the transmission arm 2 or by a transmission element, for example a transmission lever 24, which is pivotable about a pivot axis 22 within the cavity 13 and which is acted upon by an end section 5' of the transmission arm 5.

[0040] A screw tool characterized in that, in the blocking position, the pivotability of a movable element, in particular the transmission arm 5, from the rest position to the stop position is blocked by means of a blocking body 9 which rests against a blocking point 8 in the blocking position.

[0041] A screwdriving tool characterized in that the locking body 9 is attached to the transmission arm 5 by means of a positive locking element 17 and acts through a window 14 of the drive arm 2.

[0042] A screw tool characterized in that the switching element 10 is a slide which can be displaced externally along the drive arm 2 and the recess 16 and the locking parts 8 are each formed by an inner wall of the switching element 10.

[0043] A screwdriving tool characterized in that an actuating element 29 is assigned to the drive arm 2, with which the force of the energy storage device 11 determining the limiting torque can be adjusted, and / or that a freewheel lock 40 is arranged in the head 1, with which the output element 3 can be rotated stepwise in a torque transmission direction by pivoting the drive arm 2 back and forth, and / or that a locking direction of the freewheel lock 40 can be switched with a changeover switch 4. 31312PCT - 14.10.2025

[0044] All disclosed features are essential to the invention (individually, but also in combination with one another). The disclosure of this application hereby incorporates in full the disclosure content of the associated / attached priority documents (copy of the earlier application), also for the purpose of including features of these documents in the claims of the present application. The dependent claims, even without the features of a referenced claim, characterize independent inventive developments of the prior art, in particular for the purpose of filing divisional applications based on these claims. The invention specified in each claim may additionally comprise one or more of the features described above, in particular those identified by reference numerals and / or listed in the reference numeral list.The invention also relates to design forms in which individual features mentioned in the preceding description are not realized, in particular insofar as they are recognizably unnecessary for the respective purpose or can be replaced by other technically equivalent means. 31312PCT - 14.10.2025 List of reference symbols 1 head 24 transmission element, transmission 2 Drive arm lever 3 output pins, output element 25 plunger 26 extension lever 4 switches 26' pivot point, joint pin 5 Transmission arm 26" pivot point, joint pin 5' End section 27 Adjustment element 6, 6' stop flank 28 inner tube 7, 7' Stop point 29 Actuator 8 Blocking point 30 Indicator sleeve 9 blocking elements 31 recess 10 Switching element, slide 32 Positive locking element, hook 11 Energy storage device, compression spring 33 Retaining recess 12 Rotation axis 34 Cuff 13 cavities, 35 windows 13' wall, 36 windows 13" wall, 37 windows 14 windows, 38 roller bodies 15 Sleeve, inner sleeve 39 bore 16 Recess, ring groove, window 40 Freewheel lock 17 Positive locking element 18 Control slope 19 Outer sleeve 20 bore 21 cones 22 Swivel axis 23 Shoulder 31312PCT - 14.10.2025

Claims

Claims 1. Screwdriver with a drive arm (2) which projects radially from a head (1) with respect to an axis (A) and which has a driven element (3) onto which a torque can be applied by applying a force to the drive arm (2), wherein, upon reaching a preset limit torque, a stop flank (6, 6') audibly strikes a stop point (7, 7'), characterized in that the striking of the stop flank (6, 6') at the stop point (7, 7') can be blocked by moving a switching element (10) from a basic position to a blocking position.

2. Screwdriver according to claim 1, characterized in that the contact of the stop flank (6, 6') at the stop point (7, 7') can be blocked by moving a switching element (10) from the basic position to the blocking position such that contact of the stop flank (6, 6) is prevented when the preset limit torque is reached and / or exceeded. Z ) at the posting site (7, 7 Z ) is blocked.

3. Screwdriver according to claim 1 or 2, characterized by a transmission arm (5) connected to the head (1) in a rotationally fixed manner, on which a force generated by a power storage device (11) exerts a counter-torque which is overcome when the limit torque is reached, so that the transmission arm (5) held in a rest position by the power storage device (11) pivots about a rotational axis (12) relative to the drive arm (2) until the stop flank (6, 6') abuts the stop point (7, 7') in a stop position.

4. Screwdriver according to claim 3, characterized in that an actuating element (29) is assigned to the drive arm (2), with which the 31312PCT - 14.10.2025 The limiting torque determining force of the energy storage device (11) is adjustable.

5. Screwdriver according to one of the preceding claims, characterized in that the switching element (10) forms a recess (16) into which a locking element (9) can immerse to reach the stop position, wherein a locking point (8) is adjacent to the recess (16) against which the locking element (9) rests in the locking position.

6. Screwing tool according to claim 5, characterized in that the stop point (7) is formed from the bottom of the recess (16).

7. Screwing tool according to one of the preceding claims, characterized in that the stop flank (6') is formed by the transmission arm (5) or by a transmission element, for example a transmission lever (24), which is pivotable about a pivot axis (22) within the cavity (13) and which is acted upon by an end section (5') of the transmission arm (5).

8. Screwing tool according to one of the preceding claims, characterized in that in the blocking position the pivotability of a movable element, in particular the transmission arm (5) from the rest position to the stop position is blocked by means of a blocking body (9) which in the blocking position rests against a blocking point (8).

9. Screwing tool according to claim 8, characterized in that the locking body (9) is attached to the transmission arm (5) by means of a positive locking element (17) and acts through a window (14) of the drive arm (2). 31312PCT - 14.10.2025 10. Screwing tool according to one of the preceding claims, characterized in that the switching element (10) is a slide which can be displaced externally along the drive arm (2) and the recess (16) and the locking point (8) are each formed by an inner wall of the switching element (10).

11. Screwing tool according to one of the preceding claims, wherein a freewheel lock (40) is arranged in the head (1), with which the output element (3) can be rotated stepwise in a torque transmission direction by pivoting the drive arm (2) back and forth.

12. Screw tool according to claim 11, characterized in that a locking direction of the freewheel lock (40) can be switched by means of a changeover switch (4).

13. Screwing tool according to claim 11 or 12, characterized in that the freewheel lock (40) is designed as a purely direction-changing locking mechanism, and / or that the freewheel lock (40) is adjustable between a limited torque operation in which a torque below an adjustable limit torque can be transmitted, and an unlimited torque operation in which a torque corresponding to the limit torque and torques above the limit torque can be transmitted.

14. Screwing tool, characterized by one or more of the characterizing features of one of the preceding claims. 31312PCT - 14.10.2025

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