Patent Publication Number: US-2015059192-A1

Title: Power Tool Clamping Device

Description:
PRIOR ART 
     There are already known power tool clamping devices, in particular oscillation power tool clamping devices, which comprise a clamping unit that has a movably mounted force-fit clamping plane element and has an actuating element provided to move the force-fit clamping plane element for the purpose of clamping a working tool in a clamping position. 
     DISCLOSURE OF THE INVENTION 
     The invention is based on a power tool clamping device, in particular an oscillation power tool clamping device, comprising at least one clamping unit, which has at least one movably mounted force-fit clamping plane element and has at least one actuating element provided to move the force-fit clamping plane element for the purpose of clamping a working tool at least in a clamping position. 
     It is proposed that the actuating element be mounted so as to be movable relative to the force-fit clamping plane element along at least two at least substantially mutually transverse movement directions of the actuating element. The expression “movably mounted” is intended here to define, in particular, a mounting of an element relative to at least one further element, wherein the element, in particular dissociated from an elastic deformation of the element and dissociated from movement capabilities caused by a bearing clearance, has a capability to move along at least one axis, along a travel distance greater than 1 mm, preferably greater than 10 mm, and particularly preferably greater than 20 mm, and/or has a capability to move about at least one axis, by an angle greater than 10°, preferably greater than 45°, and particularly preferably greater than 60°. A “clamping unit” is to be understood here to mean, in particular, a unit that, by means of a form fit and/or by means of a force fit, secures a working tool for the purpose of performing work on the workpiece, in particular at least partially by means of the force-fit clamping plane element of the clamping unit. The expression “force-fit clamping plane element” is intended here to define, in particular, an element having at least one clamping face, which extends in a plane and which, in particular, is larger than 0.1 cm 2 , preferably larger than 0.5 cm 2 , and particularly preferably larger than 1.5 cm 2 , and which is provided to clamp the working tool, in particular the shank of the working tool, by means of a force-fit connection. In this case, the design of the clamping face of the force-fit clamping plane element is, in particular, different to that of a curved clamping face. The clamping face is thus preferably to be considered as a clamping plane in the mathematical sense, wherein, for every two points located in the clamping plane, a straight line running through these points is also located entirely in the clamping plane. “Provided” is to be understood to mean, in particular, specially designed and/or specially equipped. 
     The force-fit clamping plane element is preferably realized as a clamping jaw against which the working tool, in particular the shank of the working tool, bears or is pressed as a result of a clamping force when the force-fit clamping plane element, realized as a clamping jaw, is in a clamping position. The term “claming position” is intended here to define, in particular, a position of the force-fit clamping plane element in which the force-fit clamping plane element bears against a counter-clamping face that corresponds to the force-fit clamping plane element, to generate a clamping force. In this case, when the working tool is disposed in the clamping unit, the force-fit clamping plane element preferably bears against the working tool, in particular the shank of the working tool, and thus exerts a clamping force upon the working tool, in particular upon the shank of the working tool, to clamp the working tool. In this case, when the working tool is disposed in the clamping unit, the force-fit clamping plane element preferably bears against an outer face of the working tool, in particular of the shank of the working tool, that is at least substantially parallel to the clamping face of the force-fit clamping plane element and extends in one plane. “Substantially parallel” is to be understood here to mean, in particular, an alignment of a direction relative to a reference direction, in particular in one plane, wherein the direction deviates from the reference direction by, in particular, less than 8°, advantageously less than 5°, and particularly advantageously less than 2°. 
     The expression “actuating element” is intended here to define, in particular, an element that can be actuated directly by an operator and that is provided to influence and/or alter a process and/or a state of at least one further element that is coupled to the element, as a result of an actuation and/or as a result of an input of parameters. The actuating element is preferably realized as an actuating sleeve. It is also conceivable, however, for the actuating element to be of a different design, considered appropriate by persons skilled in the art, such as, for example, designed as an actuating knob, as an actuating lever, etc. “At least substantially transversely” is to be understood here to mean, in particular, an alignment of a plane and or of a direction, relative to a further plane and/or a further direction, that preferably deviates from a parallel alignment of the plane and/or of the direction, relative to the further plane and/or the further direction. Particularly preferably, the actuating element is mounted so as to be movable relative to the force-fit clamping plane element along at least two at least substantially mutually perpendicular movement directions of the actuating element. The expression “substantially perpendicular” is intended here to define, in particular, an alignment of a direction relative to a reference direction, wherein the direction and the reference direction, in particular as viewed in one plane, enclose an angle of 90° and the angle has a maximum deviation of, in particular, less than 8°, advantageously less than 5°, and particularly advantageously less than 2°. By means of the design of the power tool clamping device according to the invention, it is advantageously possible to achieve a self-locking function of the clamping unit as a result of the actuating element being mounted so as to be movable relative to the force-fit clamping plane element along the at least two at least substantially mutually transverse movement directions of the actuating element, in particular if the course of one of the at least two at least substantially mutually transverse movement directions of the actuating element differs from a clamping and/or release direction of the force-fit clamping plane element. Advantageously, it is thus advantageously possible to prevent unwanted release of the clamping force of the clamping unit, in particular as a result of a strong action of a reaction force during the performance of work on a workpiece by means of the working tool disposed in the clamping unit. 
     Furthermore, it is proposed that the actuating element comprise at least one threaded region, by means of which the actuating element is mounted so as to be movable relative to the force-fit clamping plane element. The actuating element, in particular during an actuation, thus executes a translational movement, on which a rotational movement is superposed. A “threaded region” is to be understood here to mean, in particular, a region of the actuating element in which at least one thread turn of a thread, in particular of an internal thread, is disposed. The threaded region of the actuating element preferably acts together with a corresponding threaded region of a driving force transmission element of the clamping unit. It is also conceivable, however, for the actuating element to be mounted in a different manner, considered appropriate by persons skilled in the art, so as to be movable relative to the force-fit clamping plane element along the at least substantially mutually transverse movement directions. In this case, for example, it is conceivable for the actuating element to be mounted by means of a cam mechanism etc. so as to be movable relative to the force-fit clamping plane element. Advantageously, a threaded region of the actuating element makes it possible, in an inexpensive and reliable manner, for the actuating element to be mounted so as to be movable along the at least two substantially mutually transverse movement directions of the actuating element. Moreover, implementation of a self-locking function of the clamping unit can be achieved through simple design means. 
     It is additionally proposed that the clamping unit have at least one positioning element, which has at least one pressing face, extending at least substantially transversely in relation to a clamping face of the force-fit clamping plane element, for acting upon the force-fit clamping plane element. The term “positioning element” is intended here to define, in particular, an element, in particular a movably mounted element, which holds a further movably mounted element, in particular the force-fit clamping plane element, in at least one position by means of an action of force, or as far as possible prevents at least one movement of the further element along at least one direction. The positioning element is mounted, in particular, so as to be translationally movable. It is also conceivable, however, for the positioning element to be mounted so as to be movable along at least two at least substantially mutually transverse directions, in particular if the positioning element is designed so as to be integral with the actuating element. “Integral with” is to be understood to mean, in particular, connected at least in a materially bonded manner, for example by a welding process, an adhesive process, an injection process and/or another process considered appropriate by persons skilled in the art, and/or, advantageously, formed in one piece such as, for example, by being produced from a casting and/or by being produced in a single- or multi-component injection process and, advantageously, from a single blank. Preferably, when the positioning element is in a mounted state, the pressing face is disposed in an inclined manner relative to the clamping face. The pressing face is preferably realized as a wedge face. It is thus possible, by simple design means, to generate a force component along a movement axis of the positioning element, and a further force component, extending at least substantially transversely in relation to the movement axis of the positioning element, for the purpose of positioning the force-fit clamping plane element. 
     Advantageously, the force-fit clamping plane element has at least one clamping positioning face, which extends at least substantially transversely in relation to the clamping face of the force-fit clamping plane element, and which is realized so as to correspond with the pressing face of the positioning element. Preferably, the clamping positioning face is disposed in an inclined manner relative to the clamping face. 
     Preferably, the clamping positioning face is realized as a wedge face. Thus, preferably by means of a combined action of the pressing face and the clamping positioning face, a wedge mechanism is realized, which is provided to move the force-fit clamping plane element into a clamping position, via the positioning element, as a result of an actuation of the actuating element. By simple design means, it is possible to achieve a movement of the force-fit clamping plane element that is at least substantially transverse in relation to a movement direction of the positioning element, for the purpose of clamping the working tool. 
     Moreover, it is proposed that the clamping unit have at least one positioning element disposed so as to be at least rotationally fixed relative to the force-fit clamping plane element. “Disposed so as to be rotationally fixed” is to be understood here to mean, in particular, a disposition of an element, in particular the positioning element, on a further element, in which a rotational movement of the element relative to a further element is prevented, at least as far as possible. The positioning element, preferably by means of a form-fit connection, is disposed so as to be rotationally fixed relative to the force-fit clamping plane element. It is also conceivable, however, for the positioning element to be disposed so as to be rotationally fixed relative to the force-fit clamping plane element by means of a force-fit connection, etc. By simple design means, a translationally movable mounting of the positioning element can be achieved by means of the design according to the invention. Moreover, advantageously, it is possible to achieve guidance of the positioning element by the force-fit clamping plane element, during a movement relative to the force-fit clamping plane element. 
     Advantageously, the clamping unit has at least one positioning element that is annular in form. It is also conceivable, however, for the positioning element to be of a different design, considered appropriate by persons skilled in the art, such as, for example, a rectangular design. Preferably, the positioning element is realized as an annular clamping disk that, on an inner diameter of the positioning element, as viewed along a movement axis of the positioning element, comprises at least one pressing face that is inclined relative to an outer face of the positioning element. Advantageously, a compact clamping unit can be realized. 
     Particularly preferably, the clamping unit has at least one positioning element, wherein the actuating element has at least one bearing contact face against which the positioning element bears in at least one state. It is also conceivable, however, for the positioning element to be realized so as to be integral with the actuating element. In this case, the actuating element is preferably movable relative to the positioning element. By simple design means, it is possible to achieve a movement of the positioning element for the purpose of positioning the force-fit clamping plane element as a result of an actuation of the actuating element. 
     Furthermore, it is proposed that the clamping unit have at least one spring element, which is provided to apply a spring force to the force-fit clamping plane element, at least along a direction at least substantially perpendicular to a clamping face of the force-fit clamping plane element. A “spring element” is to be understood to mean, in particular, a macroscopic element having at least one extent that, in a normal operating state, can be varied elastically by at least 10%, in particular by at least 20%, preferably by at least 30%, and particularly advantageously by at least 50% and that, in particular, generates a counter-force, which is dependent on a variation of the extent and preferably proportional to the variation and which counteracts the variation. An “extent” of an element is to be understood to mean, in particular, a maximum distance of two points of a perpendicular projection of the element on to a plane. A “macroscopic element” is to be understood to mean, in particular, an element having an extent of at least 1 mm, in particular of at least 5 mm, and preferably of at least 10 mm. Preferably, the spring element is realized as a helical spring. It is also conceivable, however, for the spring element to be of a different design, considered appropriate by persons skilled in the art, such as, for example, designed as a volute spring, as a disk spring, as a leg spring, etc. The design according to the invention makes it possible, advantageously, to achieve a resetting of the force-fit clamping plane element after a release of a positioning force of the positioning element, or of the actuating element, as a result of the spring force. 
     Moreover, it is proposed that the clamping unit have at least one form-fit fixing element, which is provided to engage in the working tool, at least in the clamping position. The form-fit fixing element is preferably realized as a fixing pin. In this case, the form-fit fixing element is preferably disposed in a recess of the force-fit clamping plane element. It is possible, advantageously, to achieve secure fixing, in particular form-fit fixing, of the working tool when the working tool, in particular the shank of the working tool, is disposed in the clamping unit. 
     The invention is additionally based on a power tool, in particular a portable power tool, that comprises the power tool clamping device according to the invention. A “portable power tool” is to be understood here to mean, in particular, a power tool for performing work on workpieces, that can be transported by an operator without the use of a transport machine. The portable power tool has, in particular, a mass of less than 40 kg, preferably less than 10 kg, and particularly preferably less than 5 kg. Particularly preferably, the portable power tool has at least one oscillation drive unit. The portable power tool is thus preferably realized as a saber saw. It is also conceivable, however, for the portable power tool to be of a different design, considered appropriate by persons skilled in the art, such as, for example, designed as a compass saw, as a plunge cut saw, as hedge shears, as a tiger saw, etc. Advantageously, a high degree of operating comfort can be achieved by means of the design of the power tool according to the invention. Moreover, advantageously, it is possible to ensure guidance that is as far as possible free of play, in particular in the case of work being performed on workpieces, projecting out from a wall or the like, that are to be worked along a plane that is at least substantially flush with a wall surface of the wall. It is thus possible, advantageously, to ensure a precise work result. 
     The power tool clamping device according to the invention and/or the power tool according to the invention are/is not intended in this case to be limited to the application and embodiment described above. In particular, the power tool clamping device according to the invention and/or the power tool according to the invention may have individual elements, components and units that differ in number from a number stated herein, in order to fulfill a principle of function described herein. 
    
    
     
       DRAWING 
       Further advantages are given by the following description of the drawing. The drawing shows exemplary embodiments of the invention. The drawing, the description and the claims contain numerous features in combination. Persons skilled in the art will also expediently consider the features individually and combine them to create appropriate further combinations. 
       In the drawing: 
         FIG. 1  shows a power tool according to the invention, in a schematic representation, 
         FIG. 2  shows an exploded representation of a power tool clamping device according to the invention, in a schematic representation, 
         FIG. 3  shows a sectional view of the power tool clamping device according to the invention, along the line III-III from  FIG. 2 , in a schematic representation, 
         FIG. 4  shows a sectional view, similar to  FIG. 3 , of an alternative power tool clamping device according to the invention, in a schematic representation, 
         FIG. 5  shows an exploded representation of a further alternative power tool clamping device according to the invention, in a schematic representation, 
         FIG. 6  shows a sectional view of the further alternative power tool clamping device according to the invention, along the line VI-VI from  FIG. 5 , in a schematic representation, and 
         FIG. 7  shows a sectional view, similar to  FIG. 6 , of a further alternative power tool clamping device according to the invention, in a schematic representation. 
     
    
    
     DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
       FIG. 1  shows a power tool  40   a , realized as a saber saw. The power tool  40   a  is thus realized as a portable power tool. The power tool  40   a  in this case comprises a power tool clamping device  10   a , for coupling at least one working tool  18   a  to the power tool  40   a . The working tool  18   a  is realized as a saw blade. In this case, the working tool  18   a  comprises a shank  42   a , by which the working tool  18   a  can be inserted, at least partially, into a clamping unit  12   a  of the power tool clamping device  10   a . The clamping unit  12   a  in this case has a driving force transmission element  44   a , which is provided to transmit to the working tool  18   a  a driving force generated by means of the power tool  40   a , when the working tool  18   a  is clamped in the clamping unit  12   a . The driving force transmission element  44   a  is realized as a lift rod. 
     For the purpose of generating a driving force, the power tool  40   a  comprises a drive unit  46   a  and an output unit  48   a . The drive unit  46   a  and the output unit  48   a  are provided to drive the working tool  18   a  translationally, for the purpose of performing work on a workpiece (not represented in greater detail here) by means of the power tool  40   a , when the working tool  18   a  is clamped and fixed in the power tool clamping device  10   a . The power tool  40   a  additionally has at least one drive housing  50   a  and an output housing  52   a . The drive housing  50   a  is provided to carry the drive unit  46   a . The output housing  52   a  is provided to carry the output unit  48   a . In addition, the power tool  40   a  has a handle housing  54   a , which is disposed on the drive housing  50   a  by means of a form-fit and/or force-fit connection. The power tool  40   a  in this case may comprise a damping unit (not represented in greater detail here), which is provided to isolate the handle housing  54   a  from the drive housing  50   a , as far as possible, in respect of vibration. The handle housing  54   a  in this case comprises a D-shaped grip region  56   a , on which a switching unit  58   a  is disposed, at least partially, for deactivating the power tool  40   a  and/or putting it into operation. In addition, the handle housing  54   a  is of a shell type of construction. It is also conceivable, however, for the handle housing  54   a  to be of a different design, considered appropriate by persons skilled in the art, such as, for example, a pot type of construction, or a combination of a shell type and pot type of construction. 
       FIG. 2  shows an exploded representation of the power tool clamping device  10   a  when demounted from the power tool  40   a . The power tool clamping device  10   a  comprises the clamping unit  12   a , which has at least one movably mounted force-fit clamping plane element  14   a , and at least one actuating element  16   a , which is provided to move the force-fit clamping plane element  14   a  at least into a clamping position for the purpose of clamping the working tool  18   a . The actuating element  16   a , when in a mounted state, is mounted so as to be movable relative to the force-fit clamping plane element  14   a  along at least two at least substantially mutually transverse movement directions  20   a ,  22   a  of the actuating element  16   a . For this purpose, the actuating element  16   a  comprises at least one threaded region  24   a , by means of which the actuating element  16   a  is mounted so as to be movable relative to the force-fit clamping plane element  14   a . The threaded region  24   a  is constituted by an internal thread of the actuating element  16   a . The driving force transmission element  44   a  in this case has, on a region facing toward the actuating element  16   a , an external thread  92   a  realized so as to correspond with the threaded region  24   a . The actuating element  16   a  is mounted so as to be movable, relative to the force-fit clamping plane element  14   a , translationally along a movement axis of the actuating element  16   a  and rotationally about the movement axis, by means of a combined action of the threaded region  24   a  of the actuating element  16   a  and of the external thread  92   a  of the driving force transmission element  44   a . During an actuation, the actuating element  16   a  thereby executes a translational movement, on which a rotational movement is superposed. Thus, during an actuation, the actuating element  16   a  executes a screwing motion relative to the force-fit clamping plane element  14   a.    
     Furthermore, the clamping unit  12   a  has at least one positioning element  26   a , which has at least one pressing face  30   a , extending at least substantially transversely in relation to a clamping face  28   a  of the force-fit clamping plane element  14   a , for the purpose of acting upon the force-fit clamping plane element  14   a . The force-fit clamping plane element  14   a  in this case likewise has at least one clamping positioning face  32   a , which extends at least substantially transversely in relation to the clamping face  28   a  of the force-fit clamping plane element  14   a , and which is realized so as to correspond with the pressing face  30   a  of the positioning element  26   a . The clamping positioning face  32   a  is disposed on a side of the force-fit clamping plane element  14   a  that faces away from the clamping face  28   a . The pressing face  30   a  and the clamping positioning face  32   a  of the force-fit clamping plane element  14   a  together form a wedge mechanism, by means of which the force-fit clamping plane element  14   a  can be moved in a direction at least substantially perpendicular to the clamping face  28   a , as a result of movement of the positioning element  26   a  that is at least substantially parallel to the clamping face  28   a . The pressing face  30   a  is thus realized as a wedge face. The clamping positioning face  32   a  is realized as a corresponding wedge face. The positioning element  26   a  is translationally movable relative to the force-fit clamping plane element  14   a  as the result of an actuation of the actuating element  16   a  along the at least substantially parallel to the clamping face  28   a  of the force-fit clamping plane element  14   a . The actuating element  16   a  in this case has at least one bearing contact face  34   a,  against which the positioning element  26   a  bears in at least one state. Thus, as soon as the actuating element  16   a  is actuated, the positioning element  26   a  is moved translationally by means of the actuating element  16   a,  as a result of bearing against the bearing contact face  34   a.    
     The clamping unit  12   a  additionally has a further force-fit clamping plane element  60   a,  which is of a design at least substantially similar to that of the force-fit clamping plane element  14   a . The further force-fit clamping plane element  60   a  thus has a further clamping face  62   a  and a further clamping positioning face  64   a . The further clamping face  62   a  is provided to clamp the working tool  18   a  in a force-fit manner by means of a combined action with the clamping face  28   a  of the force-fit clamping plane element  14   a . For this purpose, the force-fit clamping plane element  14   a  and the further force-fit clamping plane element  60   a  are moved toward each other, along a direction substantially perpendicular to the clamping face  28   a  and to the further clamping face  62   a,  by a translational movement of the positioning element  26   a  along a direction at least substantially parallel to the clamping face  28   a . In this case, the clamping positioning face  32   a  slides on the pressing face  30   a,  and the further clamping positioning face  64   a  slides on a further pressing face  66   a  of the positioning element  26   a . The pressing face  30   a  and the further pressing face  66   a  of the positioning element  26   a  are disposed on the positioning element  26   a  in an offset manner relative to each other, as viewed along a circumferential direction of the positioning element  26   a  extending in a plane that is at least substantially perpendicular to the clamping face  28   a . In this case, the pressing face  30   a,  the further pressing face  66   a,  the clamping positioning face  32   a  and the further clamping positioning face  64   a  may be provided with a coating that reduces friction. 
     In order to prevent, as far as possible, a rotational movement of the positioning element  26   a  relative to the force-fit clamping plane element  14   a  and relative to the further force-fit clamping plane element  60   a  as a result of a rotational movement of the actuating element  16   a  for the purpose of moving the force-fit clamping plane element  14   a  and the further force-fit clamping plane element  60   a,  the positioning element  26   a  is disposed so as to be at least rotationally fixed relative to the force-fit clamping plane element  14   a . For this purpose, the positioning element  26   a  has form-fit regions  74   a,  which are realized so as to correspond with rotational fixing regions  86   a  of the driving force transmission element  44   a,  and which are provided to produce a form fit between the positioning element  26   a  and the rotational fixing regions  86   a  of the driving force transmission element  44   a,  along a direction of rotation of the actuating element  16   a . The positioning element  26   a  is thus likewise disposed in a rotationally fixed manner relative to the further force-fit clamping plane element  60   a . The positioning element  26   a  is annular in form. The positioning element  26   a  thus encompasses the force-fit clamping plane element  14   a  and the further force-fit clamping plane element  60   a  along the direction of rotation of the actuating element  16   a.    
     The force-fit clamping plane element  14   a  is mounted in the driving force transmission element  44   a  so as to be translationally movable along the direction that is at least substantially perpendicular to the clamping face  28   a . The force-fit clamping plane element  14   a  in this case has at least one guide region  68   a.  The guide region  68   a  is realized so as to correspond with a guide receiving region  70   a  of the driving force transmission element  44   a . The guide region  68   a  and the guide receiving region  70   a  together form a dovetail guide. It is also conceivable, however, for the guide region  68   a  and the guide receiving region  70   a  together to form a guide of a different design, considered appropriate by persons skilled in the art, such as, for example, a profile rail guide, a cage rail guide, a telescopic rail guide, etc. Moreover, the further force-fit clamping plane element  60   a  is mounted in the driving force transmission element  44   a  so as to be translationally movable along a at least substantially perpendicular to the further clamping face  62   a . For this purpose, the further force-fit clamping plane element  60   a  likewise has a guide region  72   a  realized so as to correspond with the guide receiving region  70   a  of the driving force transmission element  44   a.    
     Furthermore, the clamping unit  12   a  has at least one spring element  36   a,  which is provided to apply a spring force to the force-fit clamping plane element  14   a,  at least along the direction that is at least substantially perpendicular to the clamping face  28   a  of the force-fit clamping plane element  14   a.  The force-fit clamping plane element  14   a  in this case has a spring element receiving recess  76   a,  in which the spring element  36   a  is disposed, at least partially, when in a mounted state. Moreover, the further force-fit clamping plane element  60   a  has a further spring element receiving recess  78   a,  in which the spring element  36   a  is disposed, at least partially, when in a mounted state ( FIG. 3 ). Thus, the spring element  36   a  is supported by one end on the force-fit clamping plane element  14   a  and, by a further end, the spring element  36   a  is supported on the further force-fit clamping plane element  60   a.  The spring element  36   a  is provided to move the force-fit clamping plane element  14   a  and the further force-fit clamping plane element  60   a  n opposite directions upon release of a clamping force as a result of an actuation of the actuating element  16   a.    
     In addition, the clamping unit  12   a  has at least one form-fit fixing element  38   a,  which is provided to engage in the working tool  18   a,  at least in the clamping position. The working tool  18   a  in this case has a form-fit recess  80   a,  in which the form-fit fixing element  38   a  engages in the working tool  18   a,  at least in the clamping position. The form-fit fixing element  38   a  is realized as a fixing pin. In this case, the form-fit fixing element  38   a  is fixed in a force-fitting manner, by means of a press fit, in a fixing recess  82   a  of the force-fit clamping plane element  14   a.  The form-fit fixing element  38   a,  when in a mounted state, extends at least substantially perpendicularly in relation to the clamping face  28   a  of the force-fit clamping plane element  14   a,  beyond the clamping face  28   a  ( FIG. 3 ). The further force-fit clamping plane element  60   a  in this case has a receiving recess  84   a,  which is provided to receive the form-fit fixing element  38   a,  at least partially, at least in the clamping position, as a result of engaging in the working tool  18   a.    
     Alternative exemplary embodiments are represented in  FIGS. 4 to 7 . Components, features and functions that remain substantially the same are basically denoted by the same references. To differentiate the exemplary embodiments, the letters a to d have been appended to the references of the exemplary embodiments. The description that follows is limited basically to the differences in relation to the first exemplary embodiment in  FIGS. 1 to 3 , and reference may be made to the description of the first exemplary embodiment in  FIGS. 1 to 3  in respect of components, features and functions that remain the same. 
       FIG. 4  shows a sectional view, similar to that of  FIG. 3 , of an alternative power tool clamping device  10   b.  The power tool clamping device  10   b  comprises at least one clamping unit  12   b , which has at least one movably mounted force-fit clamping plane element  14   b , and has at least one actuating element  16   b , which is provided to move the force-fit clamping plane element  14   b  at least into a clamping position for the purpose of clamping the working tool  18   b.  The actuating element  16   b  is mounted so as to be movable relative to the force-fit clamping plane element  14   b  along at least two at least substantially mutually transverse movement directions  20   b ,  22   b  of the actuating element  16   b.  Furthermore, the clamping unit  12   b  comprises a positioning element  26   b,  which is realized so as to be integral with the actuating element  16   b.  Reference may be made to the clamping unit  12   a  described in  FIGS. 1 to 3  in respect of further features and functions of the clamping unit  12   b.    
       FIG. 5  shows an exploded representation of the power tool clamping device  10   c  when demounted from a power tool (not represented in greater detail here). The power tool clamping device  10   c  comprises the clamping unit  12   c , which has at least one movably mounted force-fit clamping plane element  14   c , and at least one actuating element  16   c , which is provided to move the force-fit clamping plane element  14   c  at least into a clamping position for the purpose of clamping the working tool  18   c . The actuating element  16   c , when in a mounted state, is mounted so as to be movable relative to the force-fit clamping plane element  14   c  along at least two at least substantially mutually transverse movement directions  20   c ,  22   c  of the actuating element  16   c . The force-fit clamping plane element  14   c  is mounted in a bearing recess  88   c  of a driving force transmission element  44   c  of the clamping unit  12   c  so as to be translational along a substantially perpendicular to a clamping face  28   c  of the force-fit clamping plane element  14   c . The force-fit clamping plane element  14   c  in this case has at least one guide region  68   c . The guide region  68   c  is realized so as to correspond with a guide receiving region  70   c  of the driving force transmission element  44   c . The guide region  68   c  and the guide receiving region  70   c  together form a dovetail guide. It is also conceivable, however, for the guide region  68   c  and the guide receiving region  70   c  together to form a guide of a different design, considered appropriate by persons skilled in the art, such as, for example, a profile rail guide, a cage rail guide, a telescopic rail guide, etc. Thus, a force-fit clamping plane element  90   c  of the driving force transmission element  44   c  constitutes a further clamping face  62   c , which enables the working tool  18   c  disposed in the clamping unit  12   c  to be clamped in a force-fitting manner by means of a combined action with the clamping face  28   c  of the force-fit clamping plane element  14   c  ( FIG. 6 ). Reference may be made to the clamping unit  12   a  described in  FIGS. 1 to 3  in respect of further features and functions of the clamping unit  12   c.    
       FIG. 7  shows a sectional view, similar to that of  FIG. 3 , of a further alternative power tool clamping device  10   d . The power tool clamping device  10   d  comprises at least one clamping unit  12   d , which has at least one movably mounted force-fit clamping plane element  14   d , and has at least one actuating element  16   d , which is provided to move the force-fit clamping plane element  14   d  at least into a clamping position for the purpose of clamping the working tool  18   d . The actuating element  16   d  is mounted so as to be movable relative to the force-fit clamping plane element  14   d  along at least two at least substantially mutually transverse movement directions  20   d ,  22   d  of the actuating element  16   d . The force-fit clamping plane element  14   d  is mounted in a bearing recess  88   d  of a driving force transmission element  44   d  of the clamping unit  12   d  so as to be translational along an at least substantially perpendicular to a clamping face  28   d  of the force-fit clamping plane element  14   d . In respect of a disposition of the force-fit clamping plane element  14   d , reference may thus be made to a disposition of the force-fit clamping plane element  14   c  in  FIGS. 5 and 6  and to a design of the driving force transmission element  44   d  described in  FIGS. 5 and 6 . 
     Furthermore, the clamping unit  12   d  comprises at least one positioning element  26   d , which is disposed so as to be rotationally fixed relative to the force-fit clamping plane element  14   d . For this purpose, the positioning element  26   d  has form-fit regions  74   d , which are realized so as to correspond with an outer form of the to the force-fit clamping plane element  14   d  or to correspond with a rotational fixing region (not represented in greater detail here) of the driving force transmission element  44   d , and which are provided to produce a form fit between the positioning element  26   d  and the force-fit clamping plane element  14   d , along a direction of rotation of the actuating element  16   d . The positioning element  26   d  in this case is of an at least substantially square design. Reference may be made to the clamping unit  12   a  described in  FIGS. 1 to 3  in respect of further features and functions of the clamping unit  12   d.