DE102012007924B4 - Hand tool with a clamping device - Google Patents

Abstract

Power-driven hand tool, comprising a housing (12) with a spindle head (14), with a tool spindle (16) which can be driven about its longitudinal axis (18), in particular rotationally oscillatory, and which is formed at its tool-side end for receiving a tool (24) to be driven, and with a clamping device (32) having an integrated adjusting element (40), wherein the adjusting element (40) between a clamping position in which a male tool (24) captive on the tool spindle (16) is fixable, and a release position is displaced in which the tool (24) is releasable, wherein the clamping device (32) has at least one integrated clamping element (38; 88) which can be coupled to the adjusting element (40), and wherein the adjusting element (40) at the transition between the clamping position and causing the release position to radially disengage or engage the at least one tension member (38; 88) such that the tool (24) is in the release position via the at least one integrated clamping element (38; 88) can be supplied, wherein the at least one clamping element (38, 88) has a silhouette with a clamping contour, which in the released position is smaller than a corresponding receiving profile (78) of a male tool (24) in the engaged state and disengaged in the cocking position State that overlaps the receiving profile (78) of the received tool (24) at least in sections, characterized in that the adjusting element (40) has an inclined active surface (42), in particular a conical surface, by means of which the at least one clamping element (38; Clamping position is contacted, and that the adjusting element (40) for the transition between the clamping position and the release position substantially axially along the longitudinal axis (18) is displaceable.

Description

The invention relates to a power-driven hand tool with a housing having a spindle head, with a driven about its longitudinal axis, in particular rotationally oscillatory driven tool spindle, which is formed at its tool-side end for receiving a tool to be driven, and with a clamping device having an integrated actuator, wherein the adjusting element between a clamping position in which a male tool is captively secured to the tool spindle, and a release position is displaced, in which the tool is releasable.

Such a hand tool is about from the WO 2005/102605 A1 known. The known hand tool has a work spindle for driving a tool, wherein the tool is fixable by means of a fastening element on a tool-side end of the work spindle. Further, a displacement device is provided which is adapted to move the fastener between a release position and a clamping position. In the release position, the fastener of the work spindle is solvable. In the clamping position, the fastening element can be tensioned by a spring element against the work spindle to fix the tool.

The known hand tool can allow a quick and easy change of a tool without the need for releasing and fixing the tool separate tools, such as wrench, screwdriver, Allen key or the like. In particular, no special tools are required to be able to fix the tool to the work spindle.

When using a hand tool, such separate tools are often lost or simply left behind in a tool box. In this way, the cost of a tool change can increase significantly.

That from the WO 2005/102605 A1 Known hand tool can overcome this disadvantage in principle. However, a detachable part, namely the fastening element, is also provided in this hand tool. The fastener is released during tool change from the work spindle. In such cases, the fastener may be lost. This can also happen, for example, when the tool is released from the hand tool after use, without the fastener is again attached to the work spindle.

From the DE 10 2005 047 400 B3 a device for locking or releasing a tool by clamping wedges is known, which clamp the tool on a raised mounting flange from radially inward against the inside of a sleeve-shaped housing body. The clamping wedges are brought by an actuating member and an adjusting movement of a biased in the direction away from the tool pull rod in a release position and in a clamping position.

From the DE 20 2007 018 679 U1 An oscillation drive is known in which a tool is clamped by means of an inserted pin provided with a head.

From the US Pat. No. 7,290,968 B1 is an extension holder for a rotating tool with a collet known in which a solid, cylindrical tool can be accommodated.

From the DE 20 2007 004 324 U1 is an adapter coupling device with a hollow cylinder, in which a screwdriver can be introduced and clamped there known. The clamping takes place in that several steel balls of the adapter are pressed radially inwardly against the screwdriver.

From the US 2005/0192585 A1 For example, a surgical instrument is known having an engine assembly, an associated collet assembly and a dissection tool such as a bone saw blade. The collet assembly has a body portion with a plurality of engagement members. The dissecting tool has a tool body with a hub which is arranged in an opening formed inside the tool body. The hub has a plurality of notches which are adapted to engage with certain engagement members.

The invention has for its object to provide a power-driven hand tool that allows safe recording of a tool and a simple tool change without separate tools and as completely as possible without releasable fasteners.

This object is achieved in a power tool according to the type mentioned fact that the clamping device has at least one integrated clamping element which can be coupled to the actuator, and that the actuator at the transition between the clamping position and the release position, a radial disengagement or engagement of at least causes a clamping element, so that the tool in the release position via the at least one integrated clamping element can be fed.

Preferred developments of the invention are the subject of the dependent claims.

In accordance with the invention, the actuating element can act on the at least one integrated clamping element in such a way that a radial displacement results. In this way, the male tool is at least radially contactable in the region of a receiving opening. By way of example, the displacement may be an expansion or constriction. Radial engagement or disengagement includes motion components oriented perpendicular to the longitudinal axis. As a result of the radial displacement of the at least one integrated clamping element, tools with closed tool receiving openings can be guided substantially axially and over the at least one clamping element in the direction of the tool spindle and fixed thereto. The clamping element can be "overcome" if its silhouette from the view of a supplied tool in the release position smaller than the tool receiving opening fails. In the clamping position, the silhouette can be larger than the tool receiving opening, so that the tool is securely fixed.

The adjusting element and the at least one clamping element can be coupled to one another such that the at least one clamping element is engaged and relieved in the release position. In the clamping position, the at least one clamping element can be loaded and disengaged by the adjusting element. A reverse design is possible in principle. When changing between the clamping position and the release position, the actuating element can act with a radial component on the at least one clamping element. The radial component can act on the at least one clamping element approximately in the direction of the clamping position. In an alternative embodiment, the radial component can act on the at least one clamping element in the direction of the release position.

The male tool can be indirectly or directly on the tool spindle for conditioning and at least be biased radially by the at least one clamping element. In a preferred embodiment, the radial disengagement or engagement of the at least one clamping element further allows at least partial axial overlap of a tool receiving contour. In other words, an axial position securing against loosening of the tool spindle can result for the tool receiving opening due to the displacement of the at least one integrated clamping element.

As an alternative or in addition, the radial disengagement or engagement of the at least one tensioning element can result in an at least partially form-fitting rotation lock against rotation about the longitudinal axis. In the preferred embodiment as a hand tool with a rotary oscillatory output high-frequency jerky and jerky loads act on the tool. With the at least partially positive rotation for the tool whose fixation can be further optimized.

The at least one clamping element can in principle be integrated in the tool spindle. It is also conceivable to perform the at least one clamping element as a separate part and to couple with the tool spindle.

According to the invention, the adjusting element has an inclined active surface, in particular a cone surface, by means of which the at least one clamping element can be contacted, wherein the adjusting element for the transition between the clamping position and the release position is substantially axially displaceable along the longitudinal axis.

By means of the inclined active surface, a substantially axial adjusting movement can be used to effect the radial disengagement or engagement of the at least one clamping element. By way of example, the adjusting element can be funnel-shaped or cone-shaped. Other designs are conceivable. The adjusting element, in particular its inclined active surface, may have approximately the shape of a pyramid, a truncated pyramid, a spherical segment or an ellipsoidal segment. It is understood that only a partial surface of the actuating element can be designed as an inclined active surface. The inclined active surface may have recesses and interruptions. It can be provided a plurality of inclined active surfaces at the actuator. The inclined active surface is inclined in particular with respect to the longitudinal axis.

The inclined active surface may be formed as an outer surface on the adjusting element. The active surface designed as an outer surface can in principle interact with, for example, a contact surface of the at least one clamping element, which is designed as an inner surface. In the reverse manner, the inclined active surface may be formed as an inner surface on the adjusting element. The inclined active surface formed as an inner surface can cooperate with a contact surface on the at least one clamping element, which is designed as an outer surface.

According to a preferred embodiment, the at least one clamping element and the control element are captively integrated into the hand tool.

The ability of the at least one clamping element for radial displacement allows basically an axial feeding of a tool with a closed tool receiving opening. In this case, the (indented) at least one clamping element can be overcome, which is in a release position. Subsequently, a displacement of the actuating element in the clamping position can cause a transfer, such as disengagement, of the at least one clamping element in its clamping position. In this way, it is not necessary to completely solve the at least one clamping element in a tool change of the tool spindle. The risk of component loss can almost be ruled out. The operation of the hand tool, especially the tool change, can be significantly simplified and made safer.

According to a further embodiment, the active surface of the adjusting element is designed as a conical surface, which tapers in the direction of a drive-side end of the tool spindle, wherein the actuating element for the transition from the release position to the clamping position axially in the direction of the drive-side end of the tool spindle is movable.

The drive end of the tool spindle is the end facing away from the tool end. The cone surface may have a (fictitious) tip, which lies approximately on the longitudinal axis. The contact surface of the at least one tensioning element can be suitably adapted to the conical surface. An actuating movement can in particular be applied to the actuating element via the drive-side end of the tool spindle.

An adjusting movement, which comprises an axial displacement of the actuating element in the direction of the drive-side end of the tool spindle, may allow, for example, a widening (disengagement) of the at least one actuating element and consequently a radial contacting of the tool.

According to an alternative embodiment, the active surface of the actuating element is designed as a conical surface, which widens in the direction of a drive-side end of the tool spindle, wherein the actuating element for the transition from the clamping position to the release position axially in the direction of the drive-side end of the tool spindle is movable.

In a modification to the aforementioned embodiment, the active surface of the actuating element and the contact surface of the at least one clamping element with respect to the longitudinal axis may be oriented inversely. In this way, the adjusting element can be brought into the clamping position by an axial displacement in the direction of the tool-side end of the tool spindle in order to disengage or widen the at least one clamping element radially.

According to a further embodiment, the tool spindle has a holding section, which has a spindle-side axial stop surface for the tool 24 provides.

The spindle-side axial stop surface can receive the tool on its side facing the housing of the hand tool in a defined axial position. The spindle-side axial stop surface may further comprise positive-locking elements, which are adapted to corresponding form-fitting counter-elements of the tool. These may be, for example, mutually corresponding projections and recesses which have matched profiles. Thus, at least one preferred position (rotational position) can be defined for the tool. In a preferred manner, a plurality of defined rotational positions are given for the tool, in which the tool is secured in a form-fitting manner against a relative rotation with respect to the tool spindle about the longitudinal axis.

According to a development of this embodiment, the holding section is formed with the spindle-side axial stop surface on at least one clamping element itself.

In this way, the holding section can perform the at least partially radial displacement of the at least one clamping element.

According to a further aspect, the at least one clamping element is designed as a collet, which preferably has a plurality of circumferentially arranged clamping sections which are interrupted by cuts.

The clamping element designed as a collet can be provided on an inner surface with the contact surface, which cooperates with the active surface of the actuating element. The active surface and the contact surface are preferably formed as conical surfaces, wherein the active surface can be configured as an outer cone and the contact surface as an inner cone. An axial relative movement between the active surface and the contact surface can cause the radial displacement of the at least one clamping element.

According to one embodiment of this embodiment, the at least one clamping element is at least partially elastic, wherein the clamping portions are at least partially radially displaceable.

The at least one tensioning element is preferably made of a material having a high elastic limit. In this way, the at least one clamping element when changing between the clamping position and the release position can be deformed to a considerable extent, without resulting in permanent deformation. The clamping portions can be bent radially outward (disengaged) at the transition between the release position and the clamping position of the active surface of the actuating element.

According to a further embodiment, the at least one clamping element on an outer tool contact surface which is inclined relative to the longitudinal axis and tapers in the direction of the drive-side end of the tool spindle, and which is adapted to radially contact the male tool in the clamping position.

The tool contact surface may have a profile which is adapted to a receiving opening of the tool. By way of example, it may be a circular profile, a polygonal profile, an angular profile, a star profile, a gear profile or the like. The tool contact surface may define the silhouette of the clamping element that may be "overstressed" by the tool in the release position to be fed to and released from the tool spindle.

The taper of the tool contact surface can cause an (axial) overlap of the receiving opening of the tool by at least one clamping element in the clamping position. The tool contact surface may be formed circumferentially on at least one clamping element. The tool contact surface can be interrupted by incisions approximately analogously to the clamping sections.

According to an alternative embodiment, the at least one clamping element comprises a plurality of rolling bodies, preferably clamping balls, wherein the rolling bodies are at least partially radially displaceable.

In this embodiment, the displacement (the engagement or disengagement) of the at least one tensioning element is not effected by an elastic deformation. Rather, the rolling bodies, which are provided with the contact surfaces, are moved radially by the displacement of the actuating element. The inclined active surface of the actuating element can urge the rolling elements to the outside. The rolling elements can be accommodated in suitable recesses directly or indirectly on the tool spindle. The trained as a rolling body clamping elements can be captively integrated into the hand tool, in particular in the tool spindle. The receptacles or recesses for the rolling elements on the tool spindle can be designed as radial bores.

Trained as a rolling body clamping elements can act on the male tool in the clamping position axially and radially. In a preferred manner, the tool has partner surfaces which are designed, for example, as recesses corresponding to the rolling bodies. In this way, the rolling body and the partner surfaces can provide the positive rotation and the positive locking of the axial position of the tool on the tool spindle.

According to the invention, the at least one clamping element has a silhouette with a clamping contour, which in the released position is smaller than a corresponding receiving profile of a male tool in the engaged state and at least partially overlaps the receiving profile of the tool received in the clamping position in the disengaged state.

The receiving profile may correspond approximately to the receiving opening of the tool. As already mentioned above, it is preferable to use tools with a closed receiving opening. The clamping contour may correspond to an outline or circumference of the tool contact surface on the clamping element.

The silhouette of the clamping element can result, for example, when viewed in the axial direction, the underside of which is used to observe the tool fixed to the tool spindle. In this viewing direction, the spindle head or the housing of the hand tool are behind the tool.

According to a further embodiment, the at least one clamping element has a form-fitting contour, which is adapted to a mating contour of a tool to be defined such that in the clamping position results in a positive rotation for the tool.

The mating contour can already be embodied by the receiving profile of the tool. However, the mating contour can also comprise shape elements, which are provided in addition to the receiving profile on the tool. The positive rotation can result both in the clamping element, which is designed as a collet, as well as in the case of a plurality of clamping elements embodying rolling bodies.

According to a further embodiment, the hand tool on a spring element, which is accommodated in particular in the tool spindle and which is adapted to act on the actuating element in the direction of the clamping position.

In this way, a user must only act separately on the tensioning device to transfer them from the clamping position to the release position. The spring element can act in the clamping position tolerancing. For example, height differences or tolerances of the receiving profile of the male tools can be compensated.

According to a further aspect, the hand tool has an actuating device with an actuating element, which can be coupled to the actuating element for its displacement and is preferably designed to selectively displace the actuating element against the force of the spring element in the direction of the release position.

The adjusting element may be designed as an adjusting lever or adjusting slide and be stored in particular on the housing of the hand tool. The actuator can be contacted at least temporarily with the actuator. The coupling between the actuator and the actuator can be done directly or indirectly. The actuating element may have a control surface which is designed approximately such that a comparatively small actuating force, which is applied in a comparatively large actuating travel, is converted into a comparatively high actuating force at a comparatively small actuating travel.

• 1 eine perspektivische Ansicht eines Handwerkzeugs;
• 2a einen Längsschnitt durch ein Handwerkzeug etwa gemäß 1 im Bereich seines Spindelkopfes, wobei das Handwerkzeug eine Spannvorrichtung aufweist;
• 2b eine stark vergrößerte Teilansicht der Darstellung gemäß 2a;
• 3 eine perspektivische Teilansicht einer Werkzeugspindel mit einem Spannelement zur Aufnahme eines Werkzeugs;
• 4 eine vereinfachte schematische Teilansicht eines Werkzeugs, das mittels eines Spannelements fixiert ist, von unten her;
• 5 eine stark vereinfachte Teilansicht der Spannvorrichtung gemäß 2a in teilweise geschnittener Darstellung im Bereich des Spannelements;
• 6a eine mit 5 korrespondierende Darstellung mit einer gegenüber 5 abgewandelten Werkzeugspindel;
• 6b eine vereinfachte Ansicht auf die Werkzeugspindel mit dem Spannelement und dem Stellelement gemäß 6a von unten her;
• 7 einen seitlichen Schnitt durch einen Spindelkopf eines weiteren Handwerkzeugs, das eine Spannvorrichtung aufweist, die gegenüber der in 2a gezeigten Ausgestaltung abgewandelt ist;
• 8a, 8b zwei stark vereinfachte Teilansichten von Werkzeugen mit Aufnahmeprofilen, die mittels korrespondierender Spannelemente fixiert sind, jeweils von unten her;
• 9a einen weiteren seitlichen Schnitt durch einen Spindelkopf eines weiteren Handwerkzeugs, das eine weitere gegenüber der Darstellung in 2a abgewandelte Spannvorrichtung aufweist, wobei sich die Spannvorrichtung in der Spannstellung befindet;
• 9b eine vereinfachte Teilansicht der Spannvorrichtung gemäß 9a im Bereich des Stellelements, das mit einer Mehrzahl von Spannelementen zusammenwirkt, wobei sich die Spannvorrichtung in der Freigabestellung befindet; und
• 10a, 10b eine Ansicht von unten her und eine perspektivische Ansicht eines weiteren Werkzeugs, das ein Aufnahmeprofil aufweist, wobei das Werkzeug jeweils nur teilweise dargestellt ist.

Further features and advantages of the invention will become apparent from the following description of several preferred embodiments with reference to the drawings. Show it:

• 1 a perspective view of a hand tool;
• 2a a longitudinal section through a hand tool approximately according to 1 in the region of its spindle head, wherein the hand tool has a tensioning device;
• 2 B a greatly enlarged partial view of the illustration according to 2a ;
• 3 a partial perspective view of a tool spindle with a clamping element for receiving a tool;
• 4 a simplified schematic partial view of a tool which is fixed by means of a clamping element, from below;
• 5 a greatly simplified partial view of the clamping device according to 2a in a partially sectioned representation in the region of the clamping element;
• 6a one with 5 corresponding representation with one opposite 5 modified tool spindle;
• 6b a simplified view of the tool spindle with the clamping element and the actuator according to 6a from below;
• 7 a lateral section through a spindle head of another hand tool, which has a tensioning device, with respect to the in 2a modified embodiment shown is modified;
• 8a . 8b two highly simplified partial views of tools with receiving profiles, which are fixed by means of corresponding clamping elements, respectively from below;
• 9a a further lateral section through a spindle head of another hand tool, the other with respect to the representation in 2a having modified clamping device, wherein the clamping device is in the clamping position;
• 9b a simplified partial view of the clamping device according to 9a in the region of the actuating element, which cooperates with a plurality of clamping elements, wherein the clamping device is in the release position; and
• 10a . 10b a view from below and a perspective view of another tool having a receiving profile, wherein the tool is only partially shown.

In 1 a hand tool is shown, which is designated overall by 10. With the hand tool 10 it can be a power-driven hand tool, in particular an electric motor driven hand tool. The hand tool 10 can be configured as an oscillatory drive. A hand tool with a rotary oscillatory output can be used for a variety of sawing, cutting, trowelling, grinding or the like. Typically, such hand tools (oscillating tools) have panning frequencies in the range of about 10,000 to 25,000 oscillations per minute. The oscillations can take place at a low pivoting angle, for example, between 0.5 ° and 7 °.

However, it goes without saying that the tool 10 by way of example can also be designed as a hand tool with a temporary or fully rotary drive. Such a hand tool can be designed as an angle grinder, hand saw or the like.

The hand tool 10 has a housing 12 on, which is a spindle head 14 followed. It is understood that the spindle head 14 integral part of the housing 12 can be. It is also conceivable, the spindle head 14 modular to the housing 12 flanging. In the case 12 (and the spindle head 14 ), a power transmission device, such as a Exzenterkoppeltrieb, be included (in 1 not shown). The housing 12 may house a motor, such as an electric motor or a pneumatic motor. In the case 12 Energy storage devices may also be included. This may be the case, for example, when it comes to the hand tool 10 to a network-independent operable hand tool 10 is, in particular a hand tool 10 with an accumulator package.

In the spindle head 14 is a tool spindle 16 stored, the tool-side end of the housing 12 in the area of the spindle head 14 protrudes outwards. The tool spindle 16 can perform a driven movement, such as a rotary oscillation or a rotation about a longitudinal axis 18 , The resulting in a preferred design of the hand tool 10 oscillatory output motion resulting from the oscillation tool is illustrated by a double arrow labeled 20.

On the tool spindle 16 is a tool 24 received and by means of a fastener 22 secured. At the tool 24 it is, for example, a sawing tool or a cutting tool with a toothing with a spatially limited extent. As already mentioned above, the tool 24 However, also be designed as a grinding tool, polishing tool or the like. The tool 24 may have a crank.

A circular line designated 26 illustrates that essentially rotationally symmetrical tools can also be used, for example sanding discs, circular saw blades or the like. Especially when the hand tool 10 adapted to the tool spindle 16 can drive rotary or intermittent, circular tools 26 to apply. The housing 12 may be formed rod-shaped and in an upper region of the tool 24 turned away, a power switch 28 respectively. So a user can use the hand tool 10 hold in a rearward area and guide and the hand tool 10 via the operating switch 28 set in motion or bring to a standstill. At a rear end, the spindle head 14 facing away, has the hand tool 10 a supply line 30 on that in 1 only partially shown. By means of the supply line 30 can the hand tool 10 be coupled with a power grid, such as a power grid or an air pressure network. As already mentioned above, the hand tool 10 However, also operated independently of the mains, for example with the help of a battery pack.

Hand tools with rotary oscillatory downforce are generally highly flexible. However, this high level of flexibility can lead to the tool 24 has to be changed comparatively frequently. In known hand tools, for example, special tools or similar tools are required for a change process. One possible approach to simplifying a tool change operation can be seen to allow a tool change exclusively with "on-board resources". Known solutions suggest about fasteners that are used to change tools from the tool spindle 16 are solvable. An attachment or a release of the releasable fasteners can be done without special tools or separate tools that are not associated with the machine. However, there is still a risk that the releasable fasteners will be lost.

In hand tools with rotary oscillatory downforce act on a recorded tool 24 high forces, in particular associated with jerky or jerky loads. The high-frequency reciprocating output motion requires special measures to secure the fixing of the tool 24 on the tool spindle 16 to enable. By contrast, hand tools with exclusively rotary output have lower loads on a tool holder. In such hand tools, the tool attachment can be done in particular taking into account the direction of rotation. For example, a screw fastening for a tool can be designed such that it automatically tightens when the tool rotates. Such solutions are not suitable for hand tools with rotary oscillatory output.

Below are various advantageous embodiments of the hand tool 10 explained, in which a tool change operation can be done entirely without releasable (separable) fasteners and without separate special tools or similar aids.

In 2a is a hand tool 10 that basically the in 1 shown embodiment, in the region of the spindle head 14 shown cut. On the tool spindle 16 is a tool 24 added. For fixing the tool 24 is a tensioning device 32 intended. The tool spindle 16 is by means of a drive-side bearing 34a and a driven side bearing 34b in the spindle head 14 or in the housing 12 stored. Between the camps 34a . 34b is an eccentric fork 36 arranged non-rotatably with the tool spindle 16 connected is. The eccentric fork 36 is adapted to a drive movement of a drive motor (in 2a not shown) in a rotationally oscillatory output movement of the tool spindle 16 to convict, cf. the arrow 20 in 1 , The eccentric fork 36 may be configured to be coupled to an eccentrically rotating portion of a motor shaft, for example via a spherical bearing on the eccentric fork 36 acts.

In the 2a shown clamping device 32 is in a clamping configuration. In the clamping configuration, the tool can 24 by means of a clamping element 38 on the tool spindle 16 be fixed. An exemplary embodiment of an alternative tensioning element 38a is in 3 shown in perspective. Based on 2a and 2 B it will be apparent that by means of an actuating element 40 such on the clamping element 38 can be acted on that the clamping element 38 laterally (radially) on the tool 24 can affect its fixation. The actuator 40 is exemplified as Stellkonus. The actuator 40 has an effective surface 42 on, which can be configured as a conical surface. The effective area 42 is in the direction of a drive-side end of the tool spindle 16 rejuvenated. Towards a tool-side end of the tool spindle 16 is the effective area 42 opened or widened. The tensioning element 38 has a contact surface 44 on, with the effective area 42 corresponds. The contact surface 44 can also be configured as a cone surface. In the present case is the contact surface 44 formed as an inner cone, which extends in the direction of the drive-side end of the tool spindle 16 tapered and towards the tool end of the tool spindle 16 increases or expands. The tensioning element 38 can be an integral part of the tool spindle 16 his. Likewise, the clamping element 38 be formed as a separate part and in a suitable manner with the tool spindle 16 be connected.

For fixing or releasing the tool 24 can the clamping element 38 through the actuator 40 at least partially radially disengaged or indented. A radial component of motion is substantially perpendicular to the longitudinal axis 18 oriented. The radial disengagement or engagement can also be understood as lateral disengagement or engagement. In other words, the approximately designed as a control cone actuator 40 during its displacement in the direction of the drive-side end of the tool spindle 16 such on the trained as a collet clamping element 38 act to broaden it.

The tensioning element 38 can a plurality of clamping sections 46 have, which may be formed as clamping segments about. The clamping sections 46 can through incisions or recesses 48 be formed in the clamping element 38 are introduced. By way of example, the tensioning element 38a according to 3 four clamping sections 46 and four cuts 48 on. Deviating from this, the clamping element 38 according to 2a exemplary six clamping sections 46 as well as six cuts 48 on, cf. also the following explanations in connection with 4 ,

The clamping sections 46 and the cuts 48 Can contribute to the elastic deformability of the clamping element 38 to increase. In other words, the clamping element 38 be designed sufficiently flexible to defined by the actuator 40 to be deformed and in turn to be able to accept the initial form in a discharge. Accordingly, the actuator can 40 be sufficiently stiff and firm.

2 B shows a greatly enlarged section of the design according to 2a in the area of a tool holder. For reasons of illustration, it has been assumed that the representation in FIG 2a apart. However, this does not stand in the way of understanding. 2 B shows a section of the tool 24 that on the clamping element 38 is fixed. In the axial direction, the tool passes 24 on a holding section 50 to the plant. The holding section 50 provides an axial stop surface 52 for the tool 24 ready, cf. also 3 , The holding section 50 can basically on the tool spindle 16 be educated. In particular, the holding section 50 on the clamping element 38 be formed or integrated into this. According to the in 3 The embodiment shown is the holding section 50 at the respective clamping sections 46 intended. In other words, the holding section 50 consequently also be executed interrupted.

For radial fixation of the tool 24 is on the clamping element 38 a security section 54 formed, which has a tool contact surface 56 provides. According to the in 2 B shown embodiment, the tool contact surface 56 be formed as an inclined surface or conical surface. The tool contact surface 56 can in the direction of the drive end of the tool spindle 16 be rejuvenated. In particular, the tool contact surface 56 at an angle α opposite the longitudinal axis 18 be inclined, which is greater than an angle β, the inclination of the contact surface 44 opposite the longitudinal axis 18 describes.

The actuator 40 according to 2a also has a shaft 58 on that with a pressure piece 60 is provided. At the pressure piece 60 can a spring element 62 supported, which is adapted to the actuator 40 in the direction of the drive end of the tool spindle 16 to relocate. The spring element 62 can be configured as a helical spring, plate spring, disc spring package or the like. The spring element 62 can basically be designed as a compression spring and on the tool spindle 16 support. In principle, modifications are conceivable in which the spring element 62 is designed as a tension spring. Furthermore, a fluidic spring element can also be used 62 come to the application, such as a gas spring. On the tool spindle 16 is also a spindle stop 63 provided, the axial displacement of the pressure piece 60 and thus of the actuating element 40 relative to the tool spindle 16 limited. According to the in 2a As shown, it is not necessary that the pressure piece 60 in the clamping position of the actuating element 40 for contact with the spindle stop 63 arrives.

A user may suitably operate on the actuator 40 to relocate it, the tensioning device 32 into the clamping configuration or the release configuration. For this is the hand tool 10 according to 2a an example of an actuating device 66 provided in an appropriate manner to an operating section 64 can act. The operating section 64 can be used as an extension of the shaft 58 be formed and the tool spindle 16 protrude through at its drive end.

The actuating device 66 has an actuator 68 on, which in the present case is designed as an actuating lever. The actuator 68 has a control surface 70 on, which is configured as a cam surface or eccentric surface. The actuator 68 is about an axis 72 held pivotally, cf. a designated 74 arrow. The axis 72 is at the spindle head 14 or on the housing 12 of the hand tool 10 stored. A pivoting of the actuating element 68 around the axis 72 Overall, an axial displacement of the actuating element 40 cause, cf. one with 76 designated arrow. For this purpose, the control surface 70 suitably on a counter surface on the operating portion 64 act.

To transfer the in 2a in the clamping configuration illustrated clamping device 32 in the release configuration is the force of the spring element 62 to overcome. Conversely, the spring element carries 62 in addition, the tensioning device 32 automatically transfer from the release configuration in the clamping configuration and to keep in this.

Analogous to 2a is the actuator 40 in 2 B in its cocking position. In the clamping position, the actuator has 40 the clamping element 38 radially displaced or disengaged. By way of example, the tool contact surface 56 the tool 24 contact radially. This may be about a line contact. In principle, a point contact is also conceivable. The inclination of the tool contact surface 56 can help the tool 24 or its receiving opening in the clamping position axially overlap or axially against loosening of the tool spindle 16 to secure. In 2 B is with L _I a pass gauge indicated, which corresponds to a Aufnahmemaß about a tool receiving opening. In its release position (see also 5 ) is the security section 54 of the clamping element 38 with the tool contact surface 56 so indented that by the measure L _I characterized tool can be easily solved or supplied. In the in 2 B shown clamping position is also with L _A suggested a degree of overlap, in conjunction with the passport size L _I illustrates the area in which the clamping element 38 or its securing section 54 with the tool contact surface 56 the tool 24 axially overlap or overlap. Even if a resulting difference between the passport size L _I and the overlap L _A can be relatively small, the tool can 24 safe and accurate on the tool spindle 16 be determined. This can be done without separate fasteners that would have to be solved for example in the case of a tool change. The advantages mentioned come into play especially when tools 24 be used with closed receiving openings, so such tools 24 whose receiving openings are completely surrounded by material.

The "indirect" operation of the clamping element 38 over the actuator 40 allows it, the clamping element 38 using an available space specifically to the male tool 24 or to adjust its receiving opening. The actuation of the clamping element 38 takes over the control element 40 , in a simple way in an already existing space of the tool spindle 16 can be integrated.

The effective area 42 of the actuating cone designed as a control element 40 may have an acute opening angle. This can contribute to power amplification. By means of moderate axial forces acting on the actuator 40 act, high radial forces can be generated on the clamping element 38 act on its displacement or deformation. The opening angle is twice as large as an angle between the effective area 42 and the longitudinal axis 18 gives, compare the angle β between the contact surface 44 and the longitudinal axis 18 , According to an exemplary embodiment, the opening angle may be approximately between 20 ° and 40 °, in particular a value of approximately 30 ° is conceivable. The opening angle of the control element 40 and an opening angle of the tensioning element 38 may be suitably matched to each other.

4 shows a simplified partial representation of the tool 24 according to 2a attached to the tool spindle 16 is fixed, from below. That is, in 4 is a viewing direction of the housing 12 of the hand tool 10 facing. For illustrative purposes, however, was in 4 on the representation of the spindle head 14 or of the housing 12 omitted, which lie in this view "behind" the tool.

As already mentioned above, the tensioning element 38 six clamping sections 46 as well as six cuts 48 on. Out 4 It can also be seen that the tool 24 a closed receiving profile (also: receiving opening) 78 having. The recording profile 78 may be formed approximately circular. Areas where the recording profile 78 from the clamping sections 46 or their security sections 54 axially overlapped or overlapped are in 4 shown in dashed lines. The recording profile 78 may have a diameter about the fit L _I equivalent. Especially when the tool 24 female profiles 78 are provided, which deviate from the circular shape, the passport dimension L _I be assigned other dimensions than a diameter.

5 shows a further illustration of the clamping device 32 according to 2a in a partially sectioned representation in the region of the clamping element 38 , The actuator 40 is located in 5 in its release position, in which there is no significant or no radial force on the clamping element 38 exercises. Accordingly, the tensioning element 38 indented. The security section 54 with the tool contact surface 56 can be reduced to about a radial extent (or: silhouette), which is smaller than the fit L _I So, for example, smaller than the recording profile 78 is. In this state, the tool can 24 simply from the tool spindle 16 be solved or attached to this.

The 6a and 6b illustrate a tool spindle 16a facing the tool spindle 16 according to 2a slightly modified. The holding sections 50 that the axial abutment surfaces 52 for the tool 24 are not on the (deformable) clamping element 38 appropriate. The holding sections 50 are the part of the tool spindle 16a assigned, which is not or not essential to the actuator 40 interacts. In other words, learn the holding sections 50 according to the in 6a and 6b shown embodiment itself no significant radial displacement. In this way, can for the tool 24 always a defined axial stop on the tool spindle 16a result.

6b shows a view of the tool spindle 16a according to 6a from below, with no tools 24 is included. It will be apparent that the tensioning element 38 about six clamping sections 46 can have. The clamping sections 46 are by an equal number of cuts 48 interrupted. In 6a is just an incision 48 shown dashed (hidden). In through the incisions 48 Defined recesses can directly on the tool spindle 16a trained holding sections 50 engage or spatially extend into this. In 6b is characterized by a plurality of arrows, one of which with 80 is designated and extending radially outwardly, illustrates that the clamping portions 46 of the clamping element 38 in the clamping position by the actuator 40 can be moved radially outward to the tool 24 to be able to record safely. In 6a is the actuator 40 in the tension position.

7 shows a further lateral section through a spindle head 14 a hand tool 10 that is a tensioning device 32a that faces the tensioning device 32 according to 2a modified.

The actuator 40a has an effective surface 42a on, which can be configured as a conical surface. The effective area 42a widens in the direction of the drive end of the tool spindle 16b on. The tensioning element 38b accordingly has a contact surface 44a on, which also in the direction of the drive-side end of the tool spindle 16b extended. In other words, the effective area 42a and the contact area 44a opposite to the 2a illustrated design rotated about 180 ° or designed mirror-image. Exemplary is the clamping element 38b than into the tool spindle 16b illustrated integrated clamping element. On the tool spindle 16b can cuts 80 be provided that the deformability of the clamping element 38b can improve. The cuts 80 may be designed such that areas of reduced cross-sections arise, which may function as material joints. In this way, even at moderate force on the actuator 40a a sufficient radial displacement of the clamping element 38b or the associated security section 54 result. Also the clamping element 38b according to 7 can a plurality of clamping sections 46 have that through cuts 48 are interrupted. On the clamping element 38b is also the holding section 50 arranged, the axial stop surface 52 can provide.

At the in 7 embodiment shown causes an axial displacement of the actuating element 40a away from the drive end of the tool spindle 16b a radial disengagement of the clamping element 38b for fixing the tool 24 , For this purpose is on the tool spindle 16b the spring element 62 intended. The spring element 62 However, now acts on the pressure piece 60 on the shaft 58 of the actuating element 40b away from the drive end of the tool spindle 16b and in the direction of the output side end of the tool spindle 16b , There may also be a spindle stop 63 be provided, which may be formed here as a circlip on the tool spindle 16b is included. To release the tool 24 from the tool spindle 16b must be the actuator 40a thus against the force of the spring 62 in the direction of the drive end of the tool spindle 16b be relocated by the user. For this purpose, an actuating device 66a provided, which is an actuating element 68a has, which can be configured as well as a pivot lever as well. In contrast to the actuator 68 according to 2a is the actuator 68a according to 7 designed to pull on the actuator 40a act. This is on the operating section 64 a driver 82 trained, the approximately of a driving surface 86 on the actuator 68a during its pivoting about the axis 72 can be taken. For the operating section 64 is at the actuator 68a a breakthrough 84 intended.

At its drive-side end, the tool spindle 16b by way of example an end section 87 on, for example by means of a threaded connection or in another suitable manner to a main body of the tool spindle 16b can be flanged. It is understood that the tool spindle (s) 16 . 16b (and 16c ) basically as "integrated" tool spindle, but also as a "built" tool spindle can be designed. An "integrated" tool spindle has a small number of parts and, in particular, can be configured essentially in one piece. A "built" tool spindle regularly consists of a plurality of individual components, which are connected together to form the tool spindle.

It is understood that also actuators 68 may be provided, which are not formed as actuating lever or pivot lever. These may in particular be actuation slides. Also in 7 shown clamping device 32a can be fully integrated and captive on the tool 10 be educated.

In the 8a and 8b are exemplary two tools 24a . 24b in partial views in the area of their recording profiles 78a . 78b shown. The tools 24a . 24b have closed (or: completely enclosed) receiving openings 78a . 78b on.

The recording profile 78a at the tool 24a according to 8a is exemplary star-shaped with eight teeth. A tensioning element 38c that with the recording profile 78a can interact is in 8a hatched shown. By way of example, the tensioning element 38c four clamping sections 46 on, for example, at least in sections, in every other of the eight prongs of the receiving profile 78a can intervene. For this purpose, at the clamping sections 46 Tool contact surfaces 56a be formed, which are about legs of the teeth of the receiving profile 78a at least partially contact. Overall, thus can the clamping element 38c give a form-fitting contour, in cooperation with the star-shaped design of the receiving profile 78a , which acts as a counter contour, a positive rotation for the tool 24a result. The tool 24a can be included in a plurality of preferred positions, rotated by about 45 °.

The tool 24b according to 8b has a recording profile 78b on, which is designed as a hexagon or hexagon. The tensioning element 38d is designed to work with the recording profile 78b interact with the tool 24b to record against rotation. By way of example, the tensioning element 38d three clamping sections 46 on that through cuts 48 are interrupted. At the clamping sections 46 are tool contact surfaces 56b formed, each approximately with an edge of the hexagonal receiving profile 78b can interact. A displacement of the control element 40 can be an engagement or disengagement of the clamping sections 46 cause and thus the tool 24b selectively set or release.

To supplement the in the 8a and 8b Illustrations shown can be about the side views according to the 2a and 5 be used, wherein the modified embodiment of the clamping elements 38c and 38d to take into account.

9a shows a further side section through a hand tool 10 in the area of its spindle head 14 that is a tensioning device 32b that faces the tensioning devices 32 according to 2a and 32a according to 7 modified. 9a shows no actuator 66 , Analogously, about the actuator 66a according to 7 also at the in 9a shown embodiment used.

The tensioning device 32b has a plurality of clamping elements 88 on, which are in the present case designed as a rolling body. In particular, it may be in the clamping elements 88 act around clamping balls. The clamping elements 88 can in shots 90 on the tool spindle 16c be arranged. The pictures 90 can be as radial holes or recesses in the tool spindle 16c be introduced. The pictures 90 can be designed such that the clamping elements 88 completely captive on the tool spindle 16c are included. In particular, by means of suitable cross-sectional reductions (in 9a not shown) a lateral release of the clamping elements 88 be avoided. The tensioning device 32b according to 9a is in the clamping configuration. 9b shows a partial view of the clamping device 32b according to 9a in the release configuration.

The actuator 40b can basically be similar to the actuator 40a according to 7 be designed. Also in 2a embodiment shown can with the clamping elements 88 in the form of rolling bodies according to 9a be combined. On the control element 40b may further exemplify a frontal paragraph 92 be provided. Out 9b will be apparent that the frontal paragraph 92 in the release position of the actuating element 40b a release of the clamping elements 88 can prevent inside. It is also conceivable in principle, the actuator 40b without the paragraph 92 perform. In such a case, about the effective area 42a be extended in a suitable manner. The tool spindle 16c also has a stop 94 on, which is a displacement of the actuator 40b in the direction of the drive end of the tool spindle 16c can limit. Also the stop 94 can be a lateral release of the clamping elements 88 prevent in the release position.

An example is the tool spindle 16c according to 9a executed as a "built" tool spindle. The tool spindle 16c has a guide section 100 on, in which the shots 90 for the clamping elements 88 are introduced. This can bring manufacturing advantages and in particular simplify the assembly. The guide section 100 also has a counter surface 102 on, as a stop for the clamping element 40b can serve. The counter surface 102 can be a movement of the clamping element 40b via the tool-side end of the tool spindle 16c limit. In modification of the embodiment in 9a is the lead section 100 in 9b not shown as a separate part.

In 9a is the overlap measure L _A shown, the approximately an outer distance between two disengaged clamping elements 88 can correspond in the clamping position. 9b on the other hand illustrates the passport size L _I which may correspond approximately to a tool receiving opening. In the in 9b shown release configuration are the clamping elements 88 indented so that they are not on the side of the fit L _I protrude.

During the transition from the release position to the clamping position, the tool spindle experiences 16c no significant radial deformation. Consequently, on the tool spindle 16c the holding section 50 with the axial stop surface 52 be educated. In addition, the tool spindle 16c further a centering surface 98 which have a male tool 24 can center. To complete the design of the clamping device 32b may mutatis mutandis the above-described embodiment of the clamping device 32a according to 7 be used.

In the 10a and 10b becomes a tool 24c illustrated in partial views, in particular for combination with the clamping device 32b according to the 9a and 9b suitable. 10a shows a view of the tool 24c from below. 10b shows a perspective view of the tool 24c in the area of his admission profile 78c , The recording profile 78c can be formed in a simple manner, for example as a circular profile. Other designs are conceivable. On the tool 24c are also partner areas 96 designed to conform to the design of the clamping elements 88 are adjusted. For example, the partner areas 96 as spherical cutouts or depressions in the tool 24c are introduced, on the circumference of the receiving profile 78c are arranged. By way of example, the tool 24c six partner areas 96 on. The partner areas 96 can in particular with spherical clamping elements 88 interact. In this way, the clamping elements 88 on the one hand cause an axial projection or an axial overlap, see. the overlap measure L _A in 9a , Furthermore, the clamping elements 88 but also in the partner areas 96 indent that for the tool 24c in the clamping position a torsion-proof recording on the tool spindle 16c results. The rotation can be done positively. On the tool spindle 16c can basically have two or more clamping elements 88 be provided. By way of example, the number of clamping elements 88 to the number of partner areas 96 be adjusted. However, it is also conceivable that the number of clamping elements 88 a subset of the number of partner areas 96 equivalent.

Also in the 9a and 9b illustrated tensioning device 32b can allow a simple and quick tool change, without the need for separate or even detachable fasteners. Especially with a combination with the tool 24c can be in the clamping position for the tool 24c provide a high-strength, high-precision position assurance. The position assurance can be done both axially and against unwanted twisting.

Claims (13)

Power-driven hand tool, comprising a housing (12) with a spindle head (14), with a tool spindle (16) which can be driven about its longitudinal axis (18), in particular rotationally oscillatingly driven, and which is formed at its tool-side end for receiving a tool (24) to be driven, and with a clamping device (32) having an integrated adjusting element (40), wherein the adjusting element (40) between a clamping position in which a male tool (24) captive on the tool spindle (16) can be fixed, and a release position is displaced in which the tool (24) is releasable, wherein the clamping device (32) has at least one integrated clamping element (38; 88) which can be coupled to the adjusting element (40), and wherein the adjusting element (40) at the transition between the clamping position and causing the release position to radially disengage or engage the at least one tension member (38; 88) such that the tool (24) is in the release position via the at least one integrated clamping element (38; 88) can be supplied, wherein the at least one clamping element (38, 88) has a silhouette with a clamping contour, which in the released position is smaller than a corresponding receiving profile (78) of a male tool (24) in the engaged state and disengaged in the cocking position State that overlaps the receiving profile (78) of the received tool (24) at least in sections, characterized in that the adjusting element (40) has an inclined active surface (42), in particular a conical surface, by means of which the at least one clamping element (38; Clamping position is contacted, and that the adjusting element (40) for the transition between the clamping position and the release position substantially axially along the longitudinal axis (18) is displaceable. Hand tools (10) after Claim 1 , characterized in that the at least one clamping element (38; 88) and the adjusting element (40) are captively integrated into the hand tool (10). Hand tools (10) after Claim 1 or 2 , characterized in that the active surface (42) of the adjusting element (40) is formed as a conical surface, which tapers in the direction of a drive-side end of the tool spindle (16), and that the adjusting element (40) for the transition from the release position to the clamping position axially in the direction of the drive-side end of the tool spindle (16) is movable. Hand tools (10) after Claim 1 or 2 , characterized in that the active surface (42) of the adjusting element (40) is designed as a conical surface, which widens in the direction of a drive-side end of the tool spindle (16), and that the adjusting element (40) for the transition from the clamping position to the release position axially in the direction of the drive-side end of the tool spindle (16) is movable. Hand tool (10) according to one of the preceding claims, characterized in that the tool spindle (16) has a holding portion (50) which provides a spindle-side axial stop surface (52) for the tool (24). Hand tools (10) after Claim 5 , characterized in that the holding portion (50) with the spindle-side axial stop surface (52) on at least one clamping element (38, 88) is formed. Hand tool (10) according to one of the preceding claims, characterized in that the at least one clamping element (38; 88) is designed as a collet and preferably has a plurality of circumferentially arranged clamping portions (46) which are interrupted by notches (48). Hand tools (10) after Claim 7 , characterized in that the at least one clamping element (38, 88) is designed to be elastic at least in sections, and that the clamping sections (46) are radially displaceable at least in sections. Hand tools (10) after Claim 7 or 8th characterized in that the at least one tensioning element (38; 88) has an outer tool contact surface (56) which is inclined relative to the longitudinal axis (18) and tapers towards the drive end of the tool spindle (16) and which is adapted thereto is to contact the male tool (24) radially in the clamping position. Hand tools (10) according to one of Claims 1 to 5 , characterized in that the at least one clamping element (88) comprises a plurality of rolling bodies, preferably clamping balls, and that the rolling bodies are at least partially radially displaceable. Hand tool (10) according to one of the preceding claims, characterized in that the at least one clamping element (38; Forming contour has, which is adapted such a counter contour of a tool to be determined (24) that results in the clamping position a positive rotation for the tool (24). Hand tool (10) according to one of the preceding claims, characterized by a spring element (62) which is accommodated in particular in the tool spindle (16) and which is designed to act on the adjusting element (40) in the direction of the clamping position. Hand tool (10) according to one of the preceding claims, characterized by an actuating device (66) with an actuating element (68) which can be coupled to the adjusting element (40) for its displacement and is preferably designed to force the adjusting element (40) against the force the spring element (62) selectively to shift in the direction of the release position.

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