SCREWDRIVER TOOL WITH REVERSABLE FREEWHEEL LOCK

Description

field of technology

[0001] The invention relates to a screwdriving tool with a drive section, an output section and a freewheel lock arranged axially or functionally between them, with a bearing section carrying a switching ring, relative to which the switching ring can be displaced in an azimuthal switching direction from a central neutral position in both a left-hand and a right-hand direction of rotation into switching positions, wherein in the switching positions the output section is rotatable relative to the output section in a freewheel direction, wherein the bearing section is assigned to the output section in such a way that the switching ring is rotatable without limitation relative to the drive section in the respective freewheel direction. State of the art

[0002] WO 00 / 34012 A1 describes a screw-type screwdriver with a direction-reversible freewheel lock, in which a switching ring is arranged in the area of ​​the output section. By rotating the switching ring relative to the output section, the freewheel lock can be brought into a neutral position, allowing the output section to rotate freely in both directions relative to the input section.

[0003] Screwdrivers with such a ratchet function are also described, for example, in DE 10 2007 004 987 A1 or DE 10 2008 055 558.

[0004] From US patents 2013 / 0042723 A1, US 2006 / 0075621 A1, US 2015 / 0000472 A1 and EP 2 623 266 B1, screwdrivers are known in which a switching ring is rotatable relative to a handle for adjusting the switching positions, with stop-limiting or detent-limiting rotation. The switching direction is opposite to the freewheeling direction.

[0005] US 2007 / 0240544 A1 also describes a screw tool in which the shift ring is only adjustable to change the shift position relative to the handle. Here, the freewheel direction corresponds to the shift direction. Summary of the invention

[0006] The invention is based on the objective of improving a generic screw tool with regard to switching between the two freewheel locks.

[0007] The problem is solved by the invention specified in the claims.

[0008] First and foremost, a screw-type tool is proposed that locks the freewheel mechanism in the neutral position of both directions of rotation. This allows for one-handed operation, with the handle held in the user's hand.

[0009] In both switching positions, the switching ring can be rotated without limitation in the respective freewheeling direction, allowing it to be "twisted." By rotating the switching ring, the freewheel lock can be moved from a locked position to a freewheeling position. In particular, it is possible to switch between two freewheeling positions, in which the output section is rotatable relative to the input section in one freewheeling direction, but not in the opposite direction. According to the invention, the switching ring is rotatable without limitation in the freewheeling direction, and especially in the respective freewheeling direction. The switching ring has a dual function according to the invention. It can be used to switch the freewheel lock. Simultaneously, it can also be used to "twist." The switching ring is supported by a bearing section, for example, a bearing body.The switching ring can be switched in the azimuthal switching direction relative to this bearing body. The bearing section is preferably fixedly connected to the output section and can thus be rotated relative to the input section and rotated indefinitely in the freewheeling direction. Furthermore, it is proposed that, unlike the prior art, the switching direction corresponds to the new freewheeling direction of the output section relative to the input section that is to be achieved during switching. For example, if a switching position of the freewheel lock is to be changed from a position that allows clockwise rotation of a screw, where the freewheeling direction of the freewheel lock is the clockwise rotation direction of the output section relative to the input section, to a switching position that allows counterclockwise rotation of a screw, the switching ring must be rotated in the new freewheeling direction, which is a counterclockwise rotation direction of the output section.Similarly, when changing the freewheel lock from a position where the freewheel direction is counterclockwise to a position where the freewheel direction is clockwise, it must be turned clockwise. If the freewheel lock has a neutral position where the drive and output sections are rotationally fixed, a freewheel position is achieved by turning the shift ring either counterclockwise or clockwise. The resulting freewheel direction of the output section is then the same as the direction in which the shift ring was turned. For "twisting," the shift ring is turned in the desired "twisting direction," which corresponds to a freewheel direction. For example, if a screw with a right-hand thread is to be screwed into a corresponding thread, the shift ring is turned clockwise.According to the invention, the switching ring can be used for "twisting".

[0010] According to a preferred embodiment of the invention, it is further proposed that the switching ring, in its switching positions corresponding to a freewheel position of the freewheel lock, is latched relative to a bearing body carrying one or more locking elements by means of detent elements or rotationally locked by means of stops. The switching ring is rotatable relative to the drive section in the respective freewheel direction without limitation. By gripping the switching ring with the tip of the thumb and fingertips, the switching ring can then be rotated relative to the drive section to enable "twisting." In doing so, the locking element, which otherwise locks the freewheel lock in the opposite direction, can slide with its locking section over the teeth of the circumferential gearing. According to a preferred embodiment, the screw tool has an elongated shape.An elongated handle forming the drive section is coaxially aligned with a shaft forming the output section. A screwdriver bit profile is arranged at the end of the shaft, or the shaft forms an insertion opening for a screwdriver bit. The handle can be made of plastic and have a diameter between 1 and 5 cm. The switching ring can function as an anti-roll device by having a non-circular circumferential surface. This circumferential surface can be polygonal. The switching ring is preferably located directly where the shaft adjoins the handle. The handle can form an annular groove in its axial region adjacent to the switching ring, the groove having a diameter smaller than the outer diameter of the switching ring. The switching ring can be part of an assembly that can be inserted into a cavity open towards the end face of a handle body.In a preferred embodiment, the freewheel lock has circumferential teeth. The circumferential teeth are preferably formed by a toothed carrier that is rotationally fixed to the drive section. The output section can have a bearing section / bearing body that supports two locking elements. The bearing body is rotationally fixed to the output section. The locking elements can be acted upon by a spring element in one direction away from each other, so that locking sections of the locking elements, which may consist of one or more teeth, can engage with the teeth, which are in particular internal teeth. The switching ring has control flanks that, depending on the switching position, keep the locking section of one of the locking elements out of the teeth. The locking element preferably has the form of a lever. It can be a single-arm lever. One end of the locking element is pivotably mounted on the bearing body.The locking element forms a bearing extension with a bearing surface that extends partially onto the outer surface of a circular cylinder and is mounted in a bearing recess in the bearing body, which forms a pivot bearing. The free end of the locking element forms the locking section with one or more teeth, which, depending on the switching position, can engage with the teeth or be held out of them. The spring element that presses the two locking elements against each other can be a compression spring formed in a bearing recess in the bearing body. According to the invention, the freewheel lock can assume three switching states.From a neutral position, in which the freewheel is locked in both directions of rotation and in which torque can be transmitted from the drive section to the driven section in both directions, the shift ring can be rotated in both the left and right directions to create a freewheel direction for the freewheel in the respective direction of rotation of the shift ring. The gear carrier can have restraint elements for its rotationally fixed connection to the drive section, which give the drive section a non-circular cross-section. Preferably, the restraint elements are wings that can engage in radial recesses of the handle cavity. In a further development of the invention, it is proposed that the toothing be internal. It can be formed by a circumferential wall of a cup-shaped recess in the gear carrier.The cup-shaped recess of the gear carrier can have a bottom. In the assembled position, the bottom forms a cover surface that rests against an end face of the bearing body. This contact closes the bearing recess in which the spring element is located. The cover also provides axial closure of the swivel bearing, in which the bearing extensions of the locking elements are located. The spring element can also be a torsion element, as described below.

[0011] The invention further aims to provide a freewheel locking mechanism in which the spring elements that actuate the locking elements into the locked position occupy as little installation space as possible in the plane of the locking elements. In particular, the invention further aims to provide a screwdriver with replaceable blades, and especially blades with an insulating coating, with a freewheel locking mechanism that can be switched by means of a switching ring.

[0012] This problem is solved primarily and essentially by using a torsion spring as the spring element. It is considered advantageous if the locking element is pivotably attached to a bearing body in the manner of a pawl about an axis, with the torsion spring extending along this axis. The locking elements can pivot about the axis in a plane of extension, for example, when a toothed locking section of a locking element is disengaged from a toothed section or when a locking element is moved into a release position. The torsion spring can extend transversely to this plane of extension. The torsion spring has at least one restraint section by which it is rotationally fixed to the bearing body. The torsion spring has a further restraint section by which it is rotationally fixed to the locking element.The torsion spring is arranged in such a way that it presses the locking section of its associated locking element into the teeth of a gear carrier. When the locking element is moved into a release position by rotating a switching ring, the torsion spring is further tensioned. With such an arrangement, it is possible to increase the diameter of the central opening of the bearing body so that an interchangeable blade can be inserted into this opening, which in particular has a polygonal internal profile, as described in the aforementioned prior art. DE 102005012729 B4 is therefore included in its entirety in the disclosure scope of this patent application.

[0013] Preferably, two locking elements are provided, which can be selectively moved into a release position. However, the locking elements can also simultaneously assume a locked position in which a locking section of the locking element engages in the toothing such that the blade is rigidly coupled to the handle. If, on the other hand, only one of the two locking elements engages in the toothing, the blade can rotate freely in either one direction or the other; in the opposite direction, the blade is fixedly coupled to the handle. The freewheeling mechanism is designed such that, with the handle held, the blade can be rotated indefinitely by turning the switching ring in one direction. If the handle is turned in the same direction, the freewheeling mechanism locks, and the blade is rotated by the handle. The locking element can have a cylindrical bearing extension.This component is mounted in a bearing extension of the bearing body such that the outer surface of the bearing extension rests against the inner surface of a swivel bearing. The swivel bearing can encompass the cylindrical bearing extension by more than 180 degrees but less than 360 degrees, allowing the bearing body to rotate about an axis within a limited swivel angle. It is considered advantageous if the spring element, in particular the torsion spring, extends along the axis. It is considered particularly advantageous if two bearing elements, for example, two bearing elements in an axial arrangement, are provided. Each of the two bearing bodies can then form a swivel bearing for each of the two locking elements, whereby the swivel bearing can extend only over an axial portion of the bearing extension, so that the bearing extension is located within two swivel bearings, each formed by one of the two bearing bodies.The two pivot bearings, or a single pivot bearing, can have base surfaces that point away from each other. End faces of the bearing extension can abut these base surfaces. The base surfaces can have openings, and in particular, slot-shaped openings. The ends of a torsion spring are inserted into these openings. The torsion spring is fixedly inserted into these openings to prevent rotation. For this purpose, the openings can have a non-circular cross-sectional profile. An end section of the torsion spring can then be inserted precisely into the openings. Preferably, the torsion spring is formed from a strip-shaped steel body. However, the torsion spring can also be formed from a polygonal body. The torsion spring can have a central section with which it is fixedly connected to the locking element to prevent rotation. For this purpose, the locking element forms an opening adapted to the cross-sectional profile of the torsion spring. This opening can also be slot-shaped.It may also be provided that the end faces of a bearing extension each have clearances. The sections of the torsion spring, which twist when the locking element is rotated, extend through these clearances. The locking elements are pre-tensioned by the torsion spring, particularly in the direction of their engagement with the teeth of the gear carrier. By rotating the switching ring, the locking elements can be selectively pivoted from a locking position to a release position by further tensioning the torsion spring. The switching ring has suitable means, in particular those described above, by which the locking elements are held in the release position. Brief description of the drawings

[0014] Exemplary embodiments of the invention are explained below with reference to the accompanying drawings. These show: Fig. 1 shows a perspective view of a screwdriver-shaped screw tool, Fig. 2 shows a view of the screw tool, Fig. 3 shows a perspective view of the section along line III-III, and Fig. 3a shows an enlarged section of the screw tool. Figure 3 section shown, Fig. 4 the section according to line IV-IV in Figure 2 in a middle neutral position of a freewheel lock 3, Fig. 5 the section according to line VV in Figure 2 in the middle neutral position, Fig. 6 a representation according to Figure 4 , however, a switching ring 4 has been rotated in a switching direction S1 in a clockwise direction relative to a bearing body 10, Fig. 7 a representation according to Figure 5 in the switching position according to Figure 6, wherein together with the switching ring 4 the output section 2 can be rotated in a free-running direction F1 in a clockwise direction relative to the input section 1, Fig. 8 a representation according to Figure 4, however, the switching ring 4 has been rotated in a switching direction S2 in a counterclockwise direction relative to the bearing body 10, Fig. 9 a representation according to Figure 5 in the switching position according to Figure 6, wherein, however, the output section 2 together with the switching ring 4 can be rotated in a freewheel direction F2 in a counterclockwise direction relative to the input section 1, Fig. 10 the switching ring 4 in a top view, Fig. 11 the bearing body 10 in a top view, Fig. 12 a first exploded view of the essential elements of the embodiment, Fig. 13 a second exploded view of the essential elements of the embodiment, Fig. 14 an assembly formed from the output section 2, the bearing body 10, the gear carrier 6 and the switching ring 4, Fig. 15 the assembly according to Figure 14in a side view and Fig. 16 the assembly in an end view, Fig. 17 a second embodiment of the invention in a perspective view, Fig. 18 the second embodiment in a view, Fig. 19 the section along line XIX-XIX in Figure 18 , Fig. 20 enlarges the section along line XX-XX in Figure 19 , Fig. 21, section XXI in Figure 20 , Fig. 22 a representation according to Figure 4 , Fig. 23 a representation according to Figure 5 , Fig. 24 a representation according to Figure 6 , Fig. 25 a representation according to Figure 7 Fig. 26 an exploded view of the second embodiment, Fig. 27 two bearing bodies 10, 10' of the second embodiment in the assembled state, Fig. 28 a top view of the in Figure 27 The bearing body 10' shown in Fig. 29, section according to line XXIX-XXIX in Figure 28 and Fig. 30 an exploded view of the in the Figure 27 The bearing body shown is 10, 10'. Description of the embodiments

[0015] The embodiments shown in the figures are screwdrivers with a handle 1, made, for example, of wood or plastic, which has an elongated shape and forms a drive section. An axial cavity 34 extends in a front end face of the handle 1, with radially extending recesses 33. A ridge adjoins the end face. An annular groove 27 extends from the ridge towards a rearward crest of the handle 1.

[0016] In one embodiment not shown, the handle 1 has a different material. For example, it can be made of metal. In other embodiments not shown, the handle does not extend in one direction of rotation, but can project transversely to the direction of rotation or even be moved by means of a joint from a position lying in the direction of rotation to a position projecting transversely to the direction of rotation.

[0017] A first embodiment of the invention is described in the Figures 1 to 16 shown and described below:

[0018] The handle 1 is connected to a shaft 2, which forms a driven section, by means of a freewheel mechanism 3. The shaft 2 has a polygonal insertion opening 26 at its end opposite the tip of the handle 1 for inserting a screwdriver bit. In an embodiment not shown, the free end of the shaft 2 has a screwdriver profile, for example, a Torx profile, Phillips head profile, slotted profile, or the like. The driven profile can also be an internal or external polygon. The shaft 2 forms a core 5, which, in the assembled state, is inserted into the cavity 34. The core 5 forms a polygonal section 21, which, in the assembled state, is inserted into a polygonal cavity 23 of a bearing body 10. The bearing body 10, in turn, is inserted, in the assembled state, into a cup-shaped recess of a gear carrier 6, which is itself inserted into the cavity 34 by a rear extension.From the rear extension of the gear carrier 6, restraint elements 32, designed in a wing-like manner, project in a radial direction and can engage in the recesses 33.

[0019] The gear carrier 6 forms an internal toothing 7 with the inner wall of the cup-shaped recess. The bottom 9 of the recess has a bore 8 in which the core 5 extends. A base-like projection of the bearing body 10 also engages in the recess. A switching ring 4 is also mounted on an outer wall of the gear carrier 6. The free end of the core 5 has a circumferential groove 25 into which a clamping ring 24 engages, axially clamping the assembly, consisting of the shaft 2, bearing body 10, and gear carrier 6, together.

[0020] The bearing body 10 can be locked in three different rotational positions relative to the switching ring 4. For this purpose, the bearing body engages in the Figures 4 and 5In the illustrated switching position, a detent ball 15 engages in a detent recess 20 and holds the bearing body 10 in a central neutral position relative to the switching ring 4.

[0021] In the Figure 6 and 7 In the illustrated switching position, the detent ball 15 engages in a detent recess 20'. This switching position is determined from the position shown in the Figures 4 and 5 The illustrated switching position is achieved by rotating the switching ring 4 in the direction of arrow S1 in the Figure 6 reached. Shaft 2 can be in this switching position in a position that is in the Figure 7 The direction of rotation designated F1 can be freely rotated. The directions of rotation S1 and F1 are identical and correspond to a clockwise direction of rotation.

[0022] In the Figure 8 and 9 In the illustrated switching position, the detent ball 15 engages in a detent recess 20". This switching position is determined from the position shown in the Figures 4 and 5The illustrated switching position is changed by rotating the switching ring 4 in the direction of arrow S2. Figure 8 reached. Shaft 2 can be in one of the positions shown in the switch in this position. Figure 9 The direction of rotation designated F2 can be freely rotated. The directions of rotation S2 and F2 are identical and correspond to a counterclockwise rotation.

[0023] The detent ball 15 is acted upon in a radial outward direction by a spring element 16, wherein the spring element 16 is a compression spring that is supported on a polygonal surface 21' of the polygonal section 21. The spring element 16 can also be supported on a differently shaped base of a recess.

[0024] The following describes the freewheel mechanism 3 shown in the drawings, which is a preferred freewheel lock 3. However, the drive section 1 can also interact with the output section using a differently designed freewheel mechanism.

[0025] The freewheel lock 3 has two locking devices arranged in a mirror-symmetrical manner, each comprising a locking element 11, 11'. The two locking elements 11, 11' are designed as levers and are pivotably associated with the bearing body 10 about a pivot axis formed by a bearing extension 18. The bearing body 10 forms a recess 12 in which the locking elements 11, 11' pivotably rest, with the bearing extensions 18 each resting in pivot bearings 17 of the bearing body 10.

[0026] The bearing body 10 forms an end face 31 which, in the assembled state, rests against the base 9 of the gear carrier 6. The base 9 closes a bearing recess 14 in which the spring element 13 extends.

[0027] The edge of the cavity of the switching ring 4, in which the bearing body 10 and the gear carrier 6 are located, also has rotation stops 36 which interact with stops 37 of the rear projection of the bearing body 10. The stops 37 are formed by edges of a recess 37' which is arranged axially offset from the recess 12.

[0028] The locking elements 11, 11' form a locking section 19 at their free ends with several teeth. In a locked position, the locking element 11, 11' engages the teeth 7 in such a way that the gear carrier 7 can only rotate in one direction relative to the bearing body 10. In this direction of rotation, the teeth of the locking section 19 slide over the teeth of the gear 7.

[0029] The edge of the cavity of the switching ring 4 forms control flanks 38, which, on the way to reaching the operating position of the Figure 6 and 7 or 8 and 9each of the two locking bodies 11, 11' slides along a control shoulder 39 to displace the locking section 19 of the respective locking body 11, 11' from its tooth engagement position into the toothing 7 (see Figure 7 or 9 ).

[0030] From the Figure 3a It can be seen that the bearing body 10 forms an annular shoulder 29, behind which is an annular step 28 of the switching ring 4, so that the switching ring 4 is axially restrained. A step 30 in the transition area of ​​the polygonal section 21 to the section of the core 5 having a round cross-section is engaged by an annular step of the bearing body 10, so that the bearing body 10 is axially restrained to the output section 2 or the core 5. The free end of the core forms a circumferential groove 25 in which a clamping ring 24 engages to axially restrain the gear carrier 6 to the output section 2.

[0031] In the exemplary embodiment, the toothing 7 is an internal toothing. In an exemplary embodiment not shown, the toothing 7, with which the locking elements 11, 11' interact, is an external toothing, so that the locking elements 11, 11' are not arranged radially inside the toothing 7 as shown in the figures, but radially outside the toothing. In this exemplary embodiment as well, the toothing or the toothing carrier can be provided to be rotationally fixed to the handle.

[0032] The screwdriver works as follows: In a position within the Figures 4 and 5 In the operating position shown, in which the switching ring 4 assumes a central neutral position, the locking sections 19 of both locking bodies 11, 11' engage in the toothing 7, so that the output section 2 is rotationally fixed to the input section in both directions of rotation.

[0033] Will, starting from the one in the Figures 4 and 5 In the illustrated operating position, the switching ring 4 is rotated in a clockwise direction S1, so that the Figure 6 and 7 The illustrated operating position is reached in which the output section 2, together with the shift ring 4, can rotate indefinitely in a freewheel direction F1, which is the clockwise direction. In this position, a screw can be turned in a first direction of rotation simply by rotating the shift ring 4 while holding the handle 1. To continue turning the screw with a higher torque in this first direction, the drive torque must be applied to the handle 1 instead of the shift ring. In other words, the handle must be gripped by hand and rotated in the freewheel direction, which, relative to the handle, is then the locking direction of the freewheel lock 3 in this switching position. Therefore, switching the shift ring 4 is not necessary.

[0034] Starting from the point in the Figures 4 and 5 If the switching ring 4 is rotated in a counterclockwise direction S2 in the operating position shown, then the Figure 8 and 9 The illustrated operating position is reached, in which the output section, together with the shift ring 4, can rotate freely in a different freewheel direction F2, which is a counterclockwise direction. In this position, a screw can be turned in this second direction simply by rotating the shift ring 4 in the other direction while holding the handle. To continue turning the screw with a higher torque in this second direction, only the actuation zone of the handle needs to be changed. Instead of rotating the shift ring 4, the handle 1 must be turned counterclockwise. Switching the freewheel lock is not necessary.

[0035] A second embodiment of the invention is described in the Figures 17 to 30shown and described below:

[0036] The handle 1 has an end section with a domed tip and a section forming an annular groove 27. A roll-off guard adjoins the section forming the annular groove 27. The roll-off guard is designed as a switching ring 4. The switching ring can also have the annular groove 27.

[0037] The handle 1 has a cavity in which a toothed carrier 6 is inserted. The toothed carrier 6 is rotationally fixed to the end section of the handle 1. The toothed carrier 6 has a cup-shaped opening with internal teeth 7. Restraint elements 32 project from the outer surface of the toothed carrier 6, with which the toothed carrier 6 is rotationally fixed to the handle 1. The handle 1 or the toothed carrier 6 forms a drive section 1.

[0038] The gear carrier 6 has an opening 8 which has a larger diameter than the one in the Figures 1 to 16 The gear carrier 6 shown, so that a bearing body 10' can be accommodated in the opening 8, which has a relatively large outer diameter and which in turn forms an opening 26 into which a blade 4 can be inserted, which can be exchanged for another blade 4.

[0039] A further bearing body 10 is provided, which is adjacent to bearing body 10' in an axial direction with respect to the direction of rotation of the screw tool. This bearing body 10 also has an opening into which the blade 4 can be inserted. The two bearing bodies 10, 10' form opposing functional sides, each of which forms pivot bearings 17. The pivot bearings 17 form bearing shells in which cylindrical bearing extensions 18 of locking elements 11, 11' are located. The bearing extensions 18 are rotatably located in the pivot bearings 17 but cannot be removed from the pivot bearings 17 in the radial direction. The locking elements 11, 11' thus form pawls that pivot about a pivot axis and form a locking section 19 with teeth that can engage with the teeth 7.

[0040] In an assembled state, as seen in the Figure 27As shown, the two end faces of the bearing bodies 10, 10' are in contact. In this state, the bearing extensions 18 are also axially restrained in the pivot bearings 17, 17'.

[0041] The pivot bearings 17, 17' form bottom surfaces against which end faces of the bearing extensions 18 can abut. Openings 43 are located in the bottom surfaces. In the exemplary embodiment, the openings 43 have a rectangular cross-section and are specifically designed as slots. An end 40 of a spring element 13, designed as a steel strip and forming a torsion spring, is inserted into each of the two opposing openings 43. The torsion spring 13 is thus rotationally fixed at both ends 40 in each of the two bearing bodies 10, 10'. In the assembled state, the bearing body formed by the two bearing bodies 10, 10' and in the Figure 27The depicted ensemble includes two windows 42 through which the locking sections 19 of the two locking bodies 11, 11' protrude in order to engage in the toothing 7.

[0042] The Figure 21 Figure 18 shows that the bearing extension 18 has two cavities pointing away from each other. These two cavities are formed by clearances 45 that adjoin the two end faces of the bearing extension 18. A central section 41 of the torsion spring 12 engages positively through an opening 44 of the bearing extension 18. The openings 43, 44 are oriented angularly relative to each other such that the torsion spring 12 is relaxed or slightly pre-tensioned when the locking elements 11, 11' protrude from the window 42. The locking teeth of the locking elements 11, 11' are thus subjected to the force of the pre-tensioned torsion spring 12 in the toothing 7.

[0043] As a result of this design, the insertion opening 26, which in the exemplary embodiment has a polygonal profile, can have a maximum diameter or a maximum cross-sectional area, so that a blade 5, which has a steel core 46 surrounded by insulation 48, can also be inserted into this insertion opening 26 (see Figure 23 and 25 The pivot bearings 17 have only a small radial distance to a polygonal surface of the polygonal insertion opening 26. The pivot bearings 17 are essentially diametrically opposed to each other.

[0044] The switching ring 4 has three detent recesses 20, 20', 20". By rotating the switching ring 4, control flanks 38 of the switching ring 4 are shifted such that in a central neutral position, in which a detent ball 15 lies in the detent recess 20, both locking elements 11, 11' assume their locking position, so that the blade 5 is rotationally fixed to the handle 1.

[0045] If the switching ring is rotated from this central position in either direction of rotation, corresponding to the freewheeling direction of the freewheel lock, the detent ball 15 engages in either the detent recess 20' or 20" . This results in the control flank 38 acting upon a control shoulder 39 of the locking element 11, 11', so that the locking element 11 is moved into a release position against the restoring force of the torsion spring 13, allowing the blade 5 to be freely rotated by turning the switching ring 4 in one direction.

[0046] The bearing body 10 forms locking hooks 50, which can engage a locking step 51 of the blade 5. By means of an actuating element 49, which is to be moved axially towards the handle 1, the locking hooks 50 can be released from the engaged position so that the blade 5 can be pulled out of the opening 26. A rear end of the blade 5 can be supported against a stop element 53 of the bearing body 10'.

[0047] The entire steel core 46, except for the output profile 54, is surrounded by an insulating plastic sheath 47, 48.

[0048] In the illustrated embodiment, the gear carrier 7 is non-rotatably connected to the handle 1. The locking elements 11, 11' are non-rotatably connected to the bearing body 10, 10' and the blade 5, respectively.

[0049] In an embodiment not shown, the gear carrier 7 can be non-rotatably connected to the blade 5 and the locking elements 11, 11' can be non-rotatably connected to the handle 1.

[0050] The screwdriver according to the invention has a drive section 1, which can, for example, be a handle. The screwdriver also has an output section 2, which can be a blade or a chuck for receiving a blade. A freewheel lock is functionally arranged between the drive section 1 and the output section 2. The freewheel lock has a switching ring 4, which can be rotated relative to the output section 2 to adjust the freewheel direction F1, F2. The switching ring 4 is rotationally fixed to the output section 2 such that the output section 2 can be rotated arbitrarily relative to the drive section 1 by rotating the switching ring 4. A bearing body 10, 10' supporting the switching ring 4 and the locking elements 11, 11' is rotationally fixed to the output section 2. A toothed section 7, into which the locking elements 11, 11' can engage, is located on the drive section 1. List of reference symbols

[0051] 1 Drive section, handle 23 Polygonal opening 2 Drive section, shaft 24 clamping ring 3 Freewheel lock 25 circumferential groove 4 shift ring 26 Polygonal insertion opening 5 core 27 ring throat 6 gear carrier 28 Ring stage 7 Interlocking 29 shoulder 8 Drilling 30 Level 9 Floor 31 Front surface 10 Bearing body 32 Restraint elements 10' Bearing body 33 Exclusion 11 Barrier element 34 cavity 11' Barrier element 35 Front surface 12 niche 36 Rotary stop 13 spring element 37 stop 14 Storage recess 37' niche 15 ratchet ball 38 Tax flank 16 spring element 38' Tax flank 17 swivel bearing 39 Tax shoulder 17' swivel bearing 40 End 18 Storage extension 41 mid-range 19 restricted area 42 Window 20 Rest recess 43 opening 20' Rest recess 44 opening 20" Rest recess 45 open space 21 Polygonal section 46 steel core 21' Polygonal surface 47 insulating sheathing 22 Drilling 48 insulating sheathing 49 Actuating element 50 Locking hook 51 Detent position 52 sloping flank 53 Stop element 54 Job profile F1 Freewheel direction F2 Freewheel direction S1 Switching direction S2 Switching direction

Claims

1. A screwdriving tool comprising a driving portion (1), an output portion (2) and a freewheel lock (3), which is axially or functionally arranged between the driving portion and the output portion and has a bearing section (10, 10') that carries a switching ring (4), wherein the switching ring (4) is displaceable relative to said bearing section in an azimuthal switching direction (S1, S2) from a central neutral position into switching positions in a counterclockwise rotating direction, as well as in a clockwise rotating direction, wherein the output portion (2) is respectively rotatable relative to the driving portion (1) in a freewheel direction (F1, F2) in the switching positions, and wherein the bearing section (10, 10') is assigned to the output portion (2) in such a way that the switching ring (4) is rotatable relative to the driving portion (1) without limitation in the respective freewheel direction (F1, F2), wherein the freewheel lock can assume three switching states, characterized in that the freewheel lock is locked in both rotating directions in the middle neutral position.

2. The screwdriving tool according to claim 1, characterized in that the switching ring (4) interlocks relative to the bearing section (10, 10') by means of detent elements (20', 20") or is rotationally locked by means of stops (36, 37) in the switching positions.

3. The screwdriving tool according to one of the preceding claims, characterized in that locking bodies (11, 11') carried by the bearing section (10, 10') engage into a toothing (7) assigned to the driving portion (1).

4. The screwdriving tool according to one of the preceding claims, characterized in that the driving portion (1) is a handle with a handle grasping zone and the switching ring (4) is arranged in a region of the handle that directly borders on the output portion (2) formed by a shaft.

5. The screwdriving tool according to claim 4, characterized in that the driving portion (1) forms an annular fillet (27) that borders on the switching ring (4) and the switching ring (4) has a noncircular circumferential surface that acts as a rollaway protection.

6. The screwdriving tool according to one of the preceding claims, characterized in that the freewheel lock (3) has a circumferential toothing (7), which is connected to the driving portion (1) in a rotationally fixed manner, and two locking bodies (11, 11'), which are connected to the output portion (2) in a rotationally fixed manner, wherein either one or the other locking body (11, 11') engages into the circumferential toothing (7) with a locking section (19) depending on a freewheel direction (F1, F2) adjusted by means of the switching ring (4).

7. The screwdriving tool according to claim 6, characterized in that the locking sections (19) of both locking bodies (11, 11') engage into the circumferential toothing (7) in the neutral position.

8. The screwdriving tool according to claim 6 or 7, characterized in that the locking bodies (11, 11') are respectively formed by a lever, which is supported in a pivot bearing (17) of the bearing section (10) in a pivotable manner with a bearing extension (18) and has a locking section (19) comprising one or more teeth on its free end, wherein said teeth engage or do not engage into the toothing (7) depending on the position of the freewheel lock (3), and wherein a spring element (13) supported in a bearing recess (14) of the bearing section (10) acts upon the two locking bodies (11, 11') away from one another.

9. The screwdriving tool according to one of claims 6 to 8, characterized in that the switching ring (4), which interlocks with the bearing section (10) in different freewheel positions of the freewheel lock (3) by means of detent elements (20, 20', 20"), has control flanks (38, 38') that interact with a control shoulder (39) of one of the locking bodies (11, 11') in order to keep the locking section (19) of the locking body (11, 11') out of the toothing (7).

10. The screwdriving tool according to one of claims 3 to 9, characterized in that a toothing carrier (6) carrying the toothing (7) is seated in an axial cavity (34) of the driving portion (1) in a rotationally fixed manner, wherein radially protruding restraining elements (32) of the toothing carrier (6) engage into radial recesses (33) of the driving portion (1).

11. The screwdriving tool according to one of claims 3 to 10, characterized in that the toothing (7) is an internal toothing formed by a circumferential wall of a pot-shaped depression of the toothing carrier (6), wherein the bottom (9) of said pot-shaped depression abuts on an end face (31) of the bearing section (10) and secures the spring element (13) from moving out of the bearing recess (14) and the bearing extensions (18) from moving out of the pivot bearings (17).

12. The screwdriving tool according to one of claims 8 to 11, characterized in that the spring element (13) is a torsion spring.

13. The screwdriving tool according to claim 12, characterized in that the locking body (11) is realized in the form of a pawl that is pivotable about an axis and the spring element (13) is arranged in the axis.

14. The screwdriving tool according to claim 12 or 13, characterized in that the spring element (13) is a flat, linearly extending steel body, which has a noncircular cross section at least in the region of its two ends (40) and its central region (41), or in that the spring element (13) is realized in the form of a flat steel strip.

15. The screwdriving tool according to one of the preceding claims, characterized in that the bearing section (10, 10') has a polygonal insertion opening, through which a section of a blade (5) extends, wherein the blade (5) forms a steel core (46), which has a sheathing (47, 48) of an insulating material and forms a output profile (54).