Patent Publication Number: US-10786893-B2

Title: Switching device for a portable power tool, in particular a hammer drill and/or chisel hammer

Description:
This application claims priority under 35 U.S.C. § 119 to patent application number DE 10 2016 218 535.7, filed on Sep. 27, 2016 in Germany, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     Switching devices for portable power tools, in particular for hammer drills and/or chisel hammers, are already known, wherein the known switching devices comprise at least one operating mode selection unit which has at least one movably, in particular rotatably, mounted operating element for selecting an operating mode of the portable power tools, and which switching devices comprise at least one locking unit for locking the operating element in at least one movement position of the operating element, in particular in at least one rotational position of the operating element. 
     SUMMARY 
     The disclosure is based on a switching device for a portable power tool, in particular for a hammer drill and/or chisel hammer, comprising at least one operating mode selection unit which has at least one movably, in particular rotatably, mounted operating element for selecting an operating mode of the portable power tool, and comprising at least one locking unit for locking the operating element in at least one movement position of the operating element, in particular in at least one rotational position of the operating element, which rotational position is assigned in particular to an operating mode. 
     It is proposed that the locking unit has at least one movably mounted locking element which, depending on a locking position of the locking element, triggers an electric and/or electronic signal for switching an operating mode of the portable power tool. A “locking unit” is intended to be understood as meaning in particular a unit which has at least two interacting elements, in particular locking elements, which are provided to interact with each other for locking purposes, in particular to be brought into contact such that a locking force can be transmitted via the two elements in order to secure/hold a further element in at least one movement position of the further element, in particular in order to avoid an unintentional movement of the further element. “Provided” is intended to be understood as meaning in particular specially designed and/or specially equipped. The fact that an object is provided for a certain function is intended to be understood as meaning in particular that the object carries out and/or implements said certain function in at least one use state and/or operating state. 
     The operating element is preferably mounted rotatably about a movement axis of the operating element. The movement axis of the operating element preferably runs transversely, in particular at least substantially perpendicularly, to a main axis of extent of the portable power tool and/or to a percussion axis of a percussion unit of the portable power tool. The expression “substantially perpendicularly” is intended here to define in particular an orientation of a direction relative to a reference direction, wherein the direction and the reference direction, in particular as viewed in a 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°. The locking unit is preferably provided to lock the operating element in a movement position of the operating element, in particular in at least one rotational position of the operating element, said rotational position being assigned in particular to an operating mode. The locking unit is preferably designed as a latching unit. The locking unit advantageously comprises the locking element which is designed as a latching element. In particular, the locking element is provided to interact with a latching recess of a latching contour of the locking unit in order to lock the operating element in a movement position of the operating element, in particular in at least one rotational position of the operating element, said rotational position being assigned in particular to an operating mode. The locking element is preferably mounted movably on the operating element, in particular in a translationally movable manner. A movement axis of the locking element preferably runs transversely, in particular at least substantially perpendicularly, to the movement axis of the operating element. The locking unit preferably comprises a spring element which acts upon the locking element with a spring force in the direction of a locking position, in particular in a direction directed away from the operating element. 
     The locking element is preferably provided to interact with a switching element of the switching device in order to trigger an electric and/or electronic signal for switching an operating mode of the portable power tool, in particular in a locking position of the locking element assigned to a chisel mode of the portable power tool. A “locking position of the locking element” is intended to be understood as meaning in particular a position of the locking element, in which the locking element locks the operating element in a movement position of the operating element and in particular engages in the latching contour of the locking unit, in particular engages in the latching recess of the latching contour. In the locking position of the locking element, the locking element can interact directly with the switching element, or can interact with the switching element with the interconnection of a further element, in particular an intermediate element, of the switching device. 
     In a preferred configuration of the portable power tool as a hammer drill and/or chisel hammer, the operating mode selection unit is provided in particular at least for selecting an operating mode of the portable power tool, said operating mode being designed as a drilling mode, as a hammer drill mode and/or as a chisel mode. In a drilling mode, an insertable tool is preferably rotationally drivable in a manner already known to a person skilled in the art. In a hammer drill mode, an insertable tool is preferably rotationally and percussively drivable in a manner already known to a person skilled in the art. In a chisel mode, an insertable tool is preferably drivable percussively in a manner already known to a person skilled in the art. A hammer drill and/or chisel hammer are/is included in particular in a device class having a high driving power. In order in particular in a drilling mode or in a hammer drill mode, to prevent what are referred to as rotation accidents due to blocking of the insertable tool by a reaction torque acting on the portable power tool, the portable power tool preferably has a unit, which is already known to a person skilled in the art, for determining a relative angle of rotation of a housing of the portable power tool. Examples of units for determining a relative angle of rotation are described, for example, in the documents WO 88 06 508 A3, DE 43 44 817 C2 or EP 0 666 148 A2 and DE 196 41 618 A1. In a chisel mode, for example, a risk of inadvertently occurring rotation accidents, in particular rotation accidents as already mentioned above, is low since the insertable tool is drivable only percussively. In the chisel mode, individual electric system functions of the portable power tool can preferably be set differently than in the drilling mode and/or hammer drill mode. In particular, an inadvertent switching off or a reduction in a driving power of the portable power tool in a chisel mode as a consequence of a limit value of an angle of rotation being exceeded is undesirable since a working process can be slowed down as a result. This applies in particular to applications and working processes in the chisel mode, in which an abrupt rotary movement of the portable power tool is unavoidable, for example in the event of what is referred to as “scabbling” on borders and edges of a concrete structure, when cutting wall openings by means of chisels and the like. In an advantageous manner, when the chisel mode is selected, at least the unit for determining a relative angle of rotation of a housing of the portable power tool should be deactivated, and/or individual operating parameters of the portable power tool should be changed. Reliable identification of an operating mode is therefore advantageous in order to permit reliable deactivation and/or changing of operating parameters. By means of the configuration according to the disclosure, a certain and reliable allocation of a movement position of the operating element to an operating mode of the portable power tool can advantageously be made possible in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the operating mode selection unit has at least one, in particular translationally and movably mounted intermediate element which, for triggering an electric and/or electronic signal for switching an operating mode of the portable power tool, is movable by the locking element depending on a movement of the locking element into at least one locking position of the locking element. For triggering an electric and/or electronic signal for switching an operating mode of the portable power tool, the intermediate element is preferably movable by the locking element depending on a movement of the locking element into at least one locking position of the locking element, said locking position being assigned to a chisel mode of the portable power tool. In particular, the intermediate element is provided to interact directly with the switching element of the switching device, in particular with an end of the intermediate element that faces away from the locking element. The switching element is preferably designed as a Hall sensor. A magnet element, in particular a permanent magnet, is preferably arranged on the intermediate element, and is provided for interacting with the Hall sensor in a manner already known to a person skilled in the art in order to trigger an electric and/or electronic signal. Alternatively, it is conceivable for the switching element to be designed as an electric switch, in particular as a microswitch, as an inductive proximity sensor, as a light barrier or as another switching element appearing expedient to a person skilled in the art. By means of the configuration according to the disclosure, bridging of a distance between the locking element and the switching element can be made possible in a structurally simple manner. An arrangement of the switching element at a distance from the locking element can advantageously be made possible, in particular for permitting a compact arrangement of electric and/or electronic components in an assembly which is arranged at a distance from the locking element in a housing of the portable power tool. A safety distance, such as, for example, an air gap distance, a creep distance or the like, can advantageously be observed in a structurally simple manner. Certain and reliable allocation of a movement position of the operating element to an operating mode of the portable power tool can advantageously be made possible in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the locking unit has at least one latching contour which, for locking the operating element in at least one movement position, in particular in at least one movement position which is assigned to an operating mode, of the operating element, interacts with the locking element, wherein at least the intermediate element at least partially engages in the latching contour in at least one state. The intermediate element preferably at least partially engages in a latching recess of the latching contour, said latching recess being assigned to a chisel mode. In a movement position of the operating element assigned to the chisel mode and in the locking position of the locking element assigned to the chisel mode, the locking element preferably at least partially engages in the latching recess of the latching contour, in particular in order to lock the operating element in a movement position of the operating element assigned to a chisel mode. During a movement into the locking position of the locking element, said locking position being assigned to a chisel mode, the locking element preferably at least partially moves the intermediate element out of the latching recess assigned to a chisel mode. The latching contour is preferably formed integrally with a housing, in particular with a gear housing, of the portable power tool. In particular, the latching contour is arranged under the operating element, as viewed along the movement axis of the operating element. In a state of the operating element in which the latter is arranged on the housing, in particular on the gear housing, of the portable power tool, the operating element preferably overlaps the latching contour, in particular as viewed along a direction running at least substantially parallel to the movement axis of the operating element. “Substantially parallel” is intended to be understood here as meaning in particular an orientation of a direction relative to a reference direction, in particular in a plane, wherein the direction is a deviation of in particular less than 8°, advantageously less than 5° and particularly advantageously less than 2°, in relation to the reference direction. By means of the configuration according to the disclosure, reliable actuation and/or movement of the intermediate element by means of the locking element can advantageously be made possible, in particular when the locking element moves into a locking position of the locking element, which locking position is assigned to a chisel mode of the portable power tool. Certain and reliable allocation of a movement position of the operating element to an operating mode of the portable power tool can advantageously be made possible in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     In addition, it is proposed that the operating mode selection unit has at least one spring element which acts upon the intermediate element with a spring force in the direction of the locking element. A “spring element” is intended to be understood as meaning in particular a microscopic element which has at least one extent which, in a normal operating state, is elastically changeable by at least 10%, in particular by at least 20%, preferably by at least 30% and particularly advantageously by at least 50%, and which in particular generates a counter force which is dependent on a change in the extent and is preferably proportional to the change and opposes the change. An “extent” of an element is intended to be understood as meaning in particular a maximum distance of two points of a perpendicular projection of the element onto a plane. A “macroscopic element” is intended to be understood as meaning in particular an element with an extent of at least 1 mm, in particular of at least 5 mm and preferably of at least 10 mm. The spring element is preferably designed as a compression spring, in particular as a helical compression spring. However, it is also conceivable for the spring element to have a different configuration appearing expedient to a person skilled in the art, for example a configuration as a tension spring, as a torsion spring, as a volute spring, as a leaf spring, as a leg spring or the like. Automatic resetting of the intermediate element can advantageously be made possible by means of the configuration according to the disclosure. Certain and reliable allocation of a movement position of the operating element to an operating mode of the portable power tool can advantageously be made possible in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the intermediate element has at least one contact surface which, for the movement of the intermediate element, interacts with a corresponding contact surface of the locking element depending on a movement of the locking element into at least one locking position of the locking element. The contact surface of the locking element preferably runs transversely, in particular at least substantially perpendicularly, with respect to latching surfaces of the locking element. The latching surfaces of the locking element are preferably provided to interact with borders of the latching contour that bound latching recesses of the latching contour, in order to lock the operating element in at least one movement position. Reliable movement of the intermediate element by means of the locking element can advantageously be achieved by means of the configuration according to the disclosure. Certain and reliable assignment of a movement position of the operating element to an operating mode of the portable power tool can advantageously be made possible in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the contact surface of the intermediate element encloses an angle differing from 90° with a movement axis of the intermediate element. The contact surface of the intermediate element preferably encloses an angle from an angular range of in particular 0° to 90°, of preferably 10° to 70° and of particularly preferably 20° to 50°, with a movement axis of the intermediate element. The movement axis of the intermediate element preferably runs transversely, in particular at least substantially perpendicularly, with respect to the movement axis of the operating element. The movement axis of the intermediate element preferably runs at least substantially parallel to the main axis of extent of the portable power tool and/or to the percussion axis of the percussion unit of the portable power tool. Reliable movement of the intermediate element by means of the locking element can advantageously be made possible by means of the configuration according to the disclosure. Reliable switching of an operating mode can advantageously be realized. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     In addition it is proposed that the intermediate element is designed as a push rod. The intermediate element is preferably mounted translationally movably translationally in the housing, in particular in the transmission housing, of the portable power tool. Reliable movement of the intermediate element by means of the locking element can be made possible in a structurally simple manner by means of the configuration according to the disclosure. Reliable switching of an operating mode can advantageously be realized. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the intermediate element has at least three limbs which are angled relative to one another, wherein at least two of the three limbs run at least substantially parallel to one another. The at least two of the three limbs, the limbs running at least substantially parallel to one another, preferably run at least substantially parallel to the main axis of extent of the portable power tool and/or to the percussion axis of the percussion unit of the portable power tool. One of the three limbs of the intermediate element preferably runs transversely, in particular at least substantially perpendicularly, with respect to the main axis of extent of the portable power tool and/or with respect to the percussion axis of the percussion unit of the portable power tool. However, it is also conceivable for the intermediate element to have a number of limbs differing from three, in particular limbs which are angled relative to one another.52 An arrangement of the switching element at a distance from the locking element can advantageously be made possible by means of the configuration according to the disclosure, in particular for permitting a compact arrangement of electric and/or electronic components in an assembly which is arranged at a distance from the locking element in a housing of the portable power tool. Reliable switching of an operating mode can advantageously be realized. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     Furthermore, it is proposed that the locking element has at least one actuating surface for a dynamic effect of an operator force, and at least one locking surface which is arranged offset along a movement axis of the locking element relative to the actuating surface. The locking surface of the locking element is preferably arranged in a latching recess of the latching contour in a locking position of the locking element. In particular, the locking surface of the locking element forms the contact surface of the locking element, said contact surface being provided to interact with the contact surface of the intermediate element for movement of the intermediate element. The actuating surface of the locking element is preferably arranged offset relative to the locking surface of the locking element along a direction running at least substantially parallel to the movement axis of the locking element. A compact configuration of the locking unit can advantageously be realized. Reliable switching of an operating mode can advantageously be realized. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. 
     In addition, a portable power tool, in particular a hammer drill and/or chisel hammer, with at least one switching device according to the disclosure is proposed. A “portable power tool” is intended to be understood here as meaning in particular a power tool for machining work pieces, which power tool can be transported by an operator without a transport machine. The portable power tool in particular has a mass which is smaller than 40 kg, is preferably smaller than 10 kg and is particularly preferably smaller than 5 kg. The portable power tool is preferably designed as a hammer drill and/or chisel hammer. However, it is also conceivable for the portable power tool to have a different configuration appearing expedient to a person skilled in the art, such as, for example, a configuration as a compass saw, as a multi-function grinding machine or the like. The portable power tool preferably comprises at least one percussion unit. The term “percussion unit” is intended here in particular to define a unit which has at least one component, in particular the percussion element, which is provided for generating and/or transmitting a pulse, in particular an axial percussion pulse, to an insertable tool. Such a component for generating and/or transmitting a pulse can be formed in particular by the percussion element which is designed, for example, as a percussion pin, as a beater, as a piston, in particular as a piston tube, and/or as another component appearing expedient to a person skilled in the art. The percussion element of the percussion unit is preferably designed as a percussion pin or snap head die which advantageously forms a percussion element separate from a beater of the percussion unit and comes directly into contact with the insertable tool for transmission of a pulse, in particular during operation of the hammer drill and/or chisel hammer. The percussion unit preferably has at least one further percussion element which is designed as a beater which, for transmitting a percussion pulse to the percussion element designed as a percussion pin, is moved within the guide element, in particular within the guide element designed as a hammer tube and/or as a piston tube. In order to generate a percussion pulse, the beater is preferably moved within the guide element by means of a pressure, in particular by means of an air pressure generated by a piston guided in the guide element, which is designed as a hammer tube. Certain and reliable assignment of a movement position to an operating mode can advantageously be made possible by means of the configuration according to the disclosure in order preferably to realize reliable switching of an operating mode. Reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool can advantageously be realized. Safe and reliable operation of the portable power tool can advantageously be made possible. 
     The switching device according to the disclosure and/or the portable power tool according to the disclosure are/is not intended to be limited here to the above-described use and embodiment. In particular, in order to realize a manner of operation described herein, the switching device according to the disclosure and/or the portable power tool according to the disclosure may have a number of individual elements, components and units, and also method steps differing from a number stated herein. In addition, in the case of the value ranges indicated in this disclosure, values lying within the limits mentioned are also intended to be considered to be disclosed and usable as desired. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages will emerge from the description below of the drawing. The drawing illustrates an exemplary embodiment of the disclosure. The drawing and the description contain numerous features in combination. A person skilled in the art will expediently also consider the features individually and combine them to form meaningful further combinations. 
       In the drawing: 
         FIG. 1  shows a schematic illustration of a portable power tool according to the disclosure, 
         FIG. 2  shows a schematic illustration of a detailed view of a switching device according to the disclosure of the portable power tool according to the disclosure in an operating position of the switching device assigned to a hammer drill mode, 
         FIG. 3  shows a schematic illustration of a detailed view of the switching device according to the disclosure of the portable power tool according to the disclosure in an operating position of the switching device assigned to a chisel mode, 
         FIG. 4  shows a schematic illustration of a sectional view of an operating element of an operating mode selection unit of the switching device according to the disclosure and of a locking element, which is arranged thereon, of a locking unit of the switching device according to the disclosure, 
         FIG. 5  shows a schematic illustration of a detailed view of the locking element in a locking position assigned to the hammer drill mode and of an intermediate element of the operating mode selection unit in a state unactuated by the locking element, and 
         FIG. 6  shows a schematic illustration of a detailed view of the locking element in a locking position assigned to the chisel mode and of the intermediate element of the operating mode selection unit in a state actuated by the locking element. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a portable power tool  12  which is designed as a hammer drill and/or chisel hammer. However, it is also conceivable for the portable power tool  12  to have a different configuration appearing expedient to a person skilled in the art, such as, for example, as a drilling machine, as a planing machine, as a garden machine or the like. The portable power tool  12  comprises at least one percussion unit  50 , in particular in the preferred configuration as a hammer drill and/or chisel hammer. Furthermore, the portable power tool  12  comprises a housing  52 . The housing  52  preferably comprises at least one transmission housing and at least one motor housing. The housing  52 , in particular the transmission housing, has in particular a cup-shaped configuration. However, it is also conceivable for the housing  52 , in particular the transmission housing, to have a shell-shaped configuration or a combination of cup-shaped and a shell-shaped configuration. 
     On a front region of the housing  52 , which front region in particular faces away from a main handle  54  of the portable power tool  12 , the portable power tool  12  comprises at least one tool holding fixture  56  for receiving an insertable tool  58 . The tool holding fixture  56  can have any configuration appearing expedient to a person skilled in the art, such as, for example, a configuration in the form of a clamping jaw chuck, in the form of an SDS® tool holding fixture, SDS® Plus tool holding fixture, in the form of an SDS® Max tool holding fixture or the like. The portable power tool  12  is furthermore designed with a releasable additional handle  60 . The additional handle  60  can be fastened releasably to the housing  52 , in particular to the transmission housing, via a latching connection or other connections appearing expedient to a person skilled in the art. 
     In order to generate a driving torque and in order to generate a percussion pulse by means of the percussion unit  50 , the portable power tool  12  has a drive unit  62 . Via an output unit  64  of the portable power tool  12 , a driving torque of the drive unit  62  is transmitted to the percussion unit  50  in manner already known to a person skilled in the art in order to generate a percussion pulse. However, it is also conceivable for the portable power tool  12  to be designed decoupled from the output unit  64  and for the drive unit  62  to substantially act directly on the percussion unit  50  in order to generate a percussion pulse. A percussion pulse of the percussion unit  50  is generated in a manner known to a person skilled in the art. Furthermore, the output unit  64  is used to transmit the driving torque in a manner already known to a person skilled in the art to the tool holding fixture  56  in order to generate a rotational movement of the insertable tool  58  via a guide element (not illustrated specifically here), which is configured as a hammer tube, of the percussion unit  50  and/or via a rotational carry-along element arranged on the tool holding fixture  56 . In order, in particular in a drilling mode or in a hammer drill mode of the portable power tool  12 , to prevent what are referred to as rotation accidents due to blocking of the insertable tool  58  by a reaction torque acting on the portable power tool  12 , the portable power tool  12  preferably has a unit  66 , which is already known to a person skilled in the art, for determining a relative angle of rotation of the housing  52  of the portable power tool  12 . 
     Furthermore, the portable power tool  12 , in particular the hammer drill and/or chisel hammer, comprises at least one switching device  10 . The switching device  10  for the portable power tool  12 , in particular for the hammer drill and/or chisel hammer, comprises at least one operating mode selection unit  14  which has at least one movably, in particular rotatably, mounted operating element  16  for selecting an operating mode of the portable power tool  12 . The operating element  16  is mounted movably, in particular rotatably, on the housing  52 . The operating element  16  is preferably designed as a rotary toggle. A movement axis  68 , in particular an axis of rotation, of the operating element  16  runs transversely, in particular at least substantially perpendicularly, to a main axis of extent  70  of the portable power tool  12  and/or with respect to a percussion axis  72  of the percussion unit  50 . The main axis of extent  70  preferably extends from the main handle  54  in the direction of the tool holding fixture  56 . The percussion axis  72  of the percussion unit  50  preferably extends at least substantially parallel, in particular coaxially, to an axis of rotation of the tool holding fixture  56 . In an alternative configuration of the switching device  10  that is not illustrated specifically here, it is conceivable for the operating element  16  to be mounted in a translationally movably manner and for a movement axis  68 , in particular a linear axis, of the operating element  16  to run at least substantially parallel to the main axis of extent  70  of the portable power tool  12  and/or to the percussion axis  72  of the percussion unit  50 . 
     The switching device  10  furthermore comprises at least one locking unit  18  for locking the operating element  16  in at least one movement position of the operating element  16 , in particular in at least one rotational position of the operating element  16  assigned to an operating mode of the portable power tool  12  (cf.  FIGS. 1, 4, 5 and 6 ). The locking unit  18  has at least one movably mounted locking element  20  which, depending on a locking position of the locking element  20 , triggers an electric and/or electronic signal for switching an operating mode of the portable power tool  12  (cf.  FIGS. 2, 3, 5 and 6 ). The locking element  20  is mounted movably on the operating element  16 . In particular, the locking element  20  is mounted in a translationally movable manner on, in particular in, the operating element  16  (cf.  FIGS. 1 to 4 ). The operating element  16  has a bearing recess  74  in which the locking element  20  is movably mounted. A movement axis  48  of the locking element  20  runs transversely, in particular at least substantially perpendicularly, with respect to the movement axis  68  of the operating element  16 . The locking unit  18  comprises at least one spring element  76  which acts upon the locking element  20  with a spring force acting in a direction directed away from the operating element  16  (cf.  FIG. 4 ). The spring element  76  is designed in particular as a compression spring. However, it is also conceivable for the spring element  76  to have a different configuration appearing expedient to a person skilled in the art, such as, for example, a configuration as a tension spring, as a torsion spring or the like. The spring element  76  is supported at one end on the operating element  16  and the spring element  76  is supported at a further end on the locking element  20 . The locking element  20  has a securing extension  78  which is provided to secure the locking element  20  on the operating element  16  against unintentional release from the operating element  16  (cf.  FIG. 4 ). The securing extension  78  is designed as a latching extension which interacts with a latching projection  80  of the operating element  16 . In order to permit removal of the locking element  20  from the operating element  16 , the securing extension  78  is designed to be elastically deflectable (cf.  FIG. 4 ). 
     The operating mode selection unit  14  comprises at least one movably, in particular translationally movably, mounted intermediate element  22  which, in order to trigger an electric and/or electronic signal for switching an operating mode of the portable power tool  12 , is movable by the locking element  20  into at least one locking position of the locking element  20  depending on a movement of the locking element  20  (cf.  FIGS. 2, 3, 5 and 6 ). Depending on a movement of the locking element  20 , the intermediate element  22  is preferably movable by the locking element  20  into at least one locking position of the locking element  20  assigned to a chisel mode of the portable power tool  12 . The intermediate element  22  is mounted movably, in particular translationally movable, on the housing  52 , in particular on the transmission housing. However, it is also conceivable, as an alternative or in addition to the translationally movable mounting, for the intermediate element  22  to be mounted rotatably on the housing  52 , in particular on the transmission housing. A movement axis  34  of the intermediate element  22  runs at least substantially parallel to the main axis of extent  70  of the portable power tool  12  and/or to the percussion axis  72  of the percussion unit  50 . The movement axis  34  of the intermediate element  22  runs transversely, in particular at least substantially perpendicularly, with respect to the movement axis  68  of the operating element  16 . The intermediate element  22  has at least three limbs  38 ,  40 ,  42  which are angled relative to one another, wherein at least two of the three limbs  38 ,  40 ,  42  run at least substantially parallel to one another. The intermediate element  22  is preferably designed as a push rod, in particular as an angled push rod. The operating mode selection unit  14  has at least one spring element  26  which acts upon the intermediate element  22  with a spring force in the direction of the locking element  20 . The spring element  26  of the operating mode selection unit  14  is preferably supported at at least one end on the intermediate element  22  and the intermediate element  22  is supported at a further end on the housing  52  or on an intermediate flange (not illustrated specifically here) of the portable power tool  12 . 
     The locking unit  18  has at least one latching contour  24  which, for locking the operating element  16  in at least one movement position of the operating element  16 , interacts with the locking element  20 , wherein at least the intermediate element  22  in at least one state at least partially engages in the latching contour  24 , in particular in at least one latching recess  82  of the latching contour  24 , said latching recess being assigned to a chisel mode of the portable power tool  12 . The latching contour  24  is arranged on the housing  52 , in particular on the transmission housing. The latching contour  24  comprises at least three latching recesses  82 ,  84 ,  86 . One latching recess  82  of the three latching recesses  82 ,  84 ,  86  is assigned to a chisel mode of the portable power tool  12 . One latching recess  84  of the three latching recesses  82 ,  84 ,  86  is assigned to a hammer drill mode of the portable power tool  12 . One latching recess  86  of the three latching recesses  82 ,  84 ,  86  is assigned to a drilling mode of the portable power tool  12 . 
     The locking element  20  has at least one actuating surface  44  for a dynamic effect of an operator force, and at least one locking surface  46  which is arranged offset along the movement axis  48  of the locking element  20  relative to the actuating surface  44 . At least in an unactuated state of the locking element  20 , the actuating surface  44  of the locking element  20  extends beyond an outer circumference of the operating element  16 . Convenient actuation of the locking element  20  for releasing locking of the operating element  16  in order to select an operating mode of the portable power tool  12  can advantageously be permitted by means of a movement, in particular a rotational movement, of the operating element  16 . The locking surface  46  of the locking element  20  is provided to engage, in particular latch, in one of the latching recesses  82 ,  84 ,  86 , depending on a movement position of the operating element  16 , in particular in order to lock the operating element  16  in at least one movement position, in particular in at least one movement position of the operating element  16  assigned to an operating mode. In at least one state, the intermediate element  22  at least partially engages in the latching recess  82  of the latching contour  24 , said latching recess being assigned to a chisel mode of the portable power tool  12 . 
     During engagement, in particular latching, of the locking surface  46  of the locking element  20 , the intermediate element  22  is at least partially movable out of the latching recess  82  of the latching contour  24 , said latching recess being assigned to a chisel mode of the portable power tool  12  (cf.  FIG. 6 ). The locking surface  46  of the locking element  20  preferably forms a contact surface  32  of the locking element  20  for movement of the intermediate element  22 . The intermediate element  22  has at least one contact surface  28 ,  30 , in particular two contact surfaces  28 ,  30  which are angled with respect to each other and, for a movement of the intermediate element  22 , interact with the corresponding contact surface  32  of the locking element  20  depending on a movement of the locking element  20  into at least one locking position of the locking element  20 . The contact surface  28 ,  30  of the intermediate element  22  encloses an angle  36  differing from 90° with the movement axis  34  of the intermediate element  22 . An abrupt movement of the intermediate element  22  can advantageously be very substantially avoided. A gentle transition from one position of the intermediate element  22  to a further position in which a switching element  88  of the switching device  10  is actuable by means of the intermediate element  22  can advantageously be achieved ( FIGS. 2 and 3 ). 
     In particular, the intermediate element  22  is provided to interact directly with the switching element  88  of the switching device  10 , in particular with an end of the intermediate element  22  which faces away from the locking element  20 . The switching element  88  is preferably designed as a Hall sensor. A magnet element  90 , in particular a permanent magnet, is preferably arranged on the intermediate element  22  and is provided to interact with the Hall sensor in a manner already known to a person skilled in the art in order to trigger an electric and/or electronic signal. Alternatively, it is conceivable for the switching element  88  to be designed as an electric switch, in particular as a microswitch, as an inductive proximity sensor, as a light barrier or as another switching element which appears expedient to a person skilled in the art and is actuable by means of a movement of the intermediate element  22 . By means of the configuration according to the disclosure of the switching device  10 , it can advantageously be ensured that, as a result of securely latching the locking element  20  in the latching contour  24 , reliable triggering of an electric and/or electronic signal for switching an operating mode of the portable power tool  12  is realized.