Patent Publication Number: US-2022221483-A1

Title: Rotational speed sensor, fixing device for a rotational speed sensor, receiving device for a rotational speed sensor, sensor system having a receiving device and a rotational speed sensor and method for the rotationally locked positioning of a rotational speed sensor

Description:
FIELD OF THE INVENTION 
     The present approach relates to a rotational speed sensor, a fixing device for a rotational speed sensor, a receiving device for a rotational speed sensor, a sensor system with a receiving device and a rotational speed sensor and a method for rotationally locked positioning of a rotational speed sensor. 
     BACKGROUND INFORMATION 
     German patent document DE 10 2008 054 000 B4 discusses a device for self-adjustment and a method for arranging a pulse rotational speed encoder relative to a rotor. For positionally correct installation, a contour which allows positionally correct installation is introduced either on the sensor or on a clamping sleeve. 
     SUMMARY OF THE INVENTION 
     Against this background, an object of the present approach is to create an improved rotational speed sensor, an improved fixing device for a rotational speed sensor, an improved receiving device for a rotational speed sensor, an improved sensor system with a receiving device and a rotational speed sensor and an improved method for rotationally locked positioning of a rotational speed sensor. 
     This object may be achieved by a rotational speed sensor, by a fixing device, by a receiving device, by a sensor system and ultimately by a method according to the main descriptions herein. 
     The advantages achievable with the presented approach are that stable positionally locked positioning of a rotational speed sensor is easily possible, with which an axial movement of the rotational speed sensor is optionally allowed. The movement can also be realized by a clamping sleeve, which is installed together with the rotational speed sensor. 
     A rotational speed sensor has a cylindrical sensor head with a measuring tip and a tongue. The tongue is arranged on an outer diameter of the sensor head and is formed to interact with a counter-contour of a fixing device as an anti-rotation device for the rotational speed sensor. 
     The rotational speed sensor may be an active rotational speed sensor, which can also be referred to as a pulse rotational speed encoder, for example. The sensor head of the rotational speed sensor can be formed in one piece with the measuring tip and the tongue. However, the sensor head may also have a first component in the form of a cylindrical base body and a second component, which has the measuring tip, wherein the first component and the second component are coupled to each other. The tongue may be formed in one piece with the first component or the second component. Alternatively, the tongue may be connected as a separate element to the first component or the second component. For example, the measuring tip may form a free end of the rotational speed sensor. The measuring tip may be configured to sense a rotational speed of a rotor or pole wheel, for example. For this purpose, the measuring tip may have at least one Hall sensor, which may be connected via a measurement and supply cable to provide a supply voltage. A rotational speed sensor presented here can be coupled in a rotationally locked manner by the tongue in or to the fixing device, which can be understood as a fixed machine part. The fixing device may have at least one fixing element. In this case, an axial movement of the rotational speed sensor, for example relative to the rotor or pole wheel, may still be possible. The rotational speed sensor presented here thus enables a form-fitting positionally correct installation thanks to a slightly special shape in the form of the tongue, wherein the rotational speed sensor can still be moved on one axis. The tongue, which is located directly on the sensor head, enables particularly stable form-fitting rotational locking. Thus, the tongue can also contact a surface formed directly on the axle, for example, and can fix the sensor in a rotationally locked manner. This has the advantage that both a conventional sensor and a rotationally locked sensor can be fixed in the same holder. 
     The tongue may extend radially away from the sensor head. For example, the tongue may extend radially away from a cylindrical section of the second component. One form of the tongue may be rectangular. This enables stable, form-fitting, rotationally locked fixing of the sensor head. Side surfaces of the tongue may be of a smooth form. The tongue may be formed without an extension or projection in the longitudinal direction of the sensor head. To prevent rotation of the rotational speed sensor, the tongue may contact the counter-contour or may touch the counter-contour. For example, the tongue may engage in or on the counter-contour as a rotational lock. As a result, a very stable anti-rotation lock can be created. 
     According to one embodiment, two side surfaces of the tongue may form stop surfaces for the counter-contour. The side surfaces may be two oppositely arranged and additionally or alternatively parallel side surfaces of the tongue. The two side surfaces may be arranged transverse to the longitudinal axis of the sensor head and opposite each other. This prevents the tongue from moving over the two side surfaces, whereby rotation of the rotational speed sensor is blocked. 
     The tongue may be located at an end of the sensor head remote from the measuring tip. This creates a way to easily realize the anti-rotation lock during installation. 
     It is also advantageous if an end surface of the tongue has a tongue groove as a stop surface for the counter-contour. The end surface may form an extreme free end of the tongue. For example, the end surface may be arranged transverse to the side surfaces and may connect them. The tongue groove may be recessed into the end surface as a semicircle. In such a tongue groove, only a simple fixing device with only a single fixing element such as a pin, which is inserted into the tongue groove, can be used for the anti-rotation lock to prevent lateral movement of the rotational speed sensor. 
     Alternatively, the end surface may be formed as a flat stop surface. Such a form can be realized cost-effectively. 
     A fixing device for one of the rotational speed sensors presented above has the counter-contour, which can be coupled to the tongue of the rotational speed sensor to position the rotational speed sensor with rotational locking. Here, the counter-contour and the tongue can be coupled to each other in a form-fitting manner. The fixing device may represent a fixed machine part or be rigidly fixed to a fixed machine part. In order to fix the fixing device to a fixed machine part, the fixing device may have at least one fixing element in the form of a screw, a rod, a bolt, a bearing body and additionally or alternatively a tab or may be coupled to at least one such fixing element. The fixing device may also be formed directly on the holder. 
     The counter-contour may, for example, have a flat surface with which the tab is in rotationally locked contact. Alternatively, the receiving groove for receiving the tongue or a projection for engaging in a tongue groove of the tongue or at least one extension can be formed as a counter-stop surface for the tongue. The receiving groove may, for example, have a rectangular cross-section to receive an essentially rectangular tongue. The receiving groove may be formed, for example, in a fixing element in the form of a bearing body. The protrusion may be, for example, a curved or angular outer surface of a rod-shaped fixing element, wherein the rod can be inserted into the tongue groove. The counter-contour may also include two of the extensions, which can act on two sides as two counter-stop surfaces for two side surfaces of the tongue. The tongue may, for example, be arranged between the two extensions to prevent lateral movement of the tongue by the two extensions in a form-fitting manner. One of the extensions or both extensions may be in the form of a rod shape. 
     A receiving device for one of the rotational speed sensors presented above has a receiving body for receiving at least one section of the sensor head and one of the fixing devices presented above. The receiving body may classically be a bore in the axle for receiving the sensor. Or in a further version the receiving body may also be of a hollow cylindrical, for example tubular form. The receiving body may be formed to be mounted on a vehicle, for example a truck or trailer. For example, an outer surface of the receiving body may have one or more welding tabs. Such a receiving device creates a stable and protected receiving option for rotationally locked mounting of the rotational speed sensor. 
     The receiving body of the receiving device and the fixing device may be formed in one piece, or the fixing device may be connected to the receiving body in a form-fitting, force-locking and additionally or alternatively firmly bonded manner. The fixing device may be screwed, clamped, glued, cast or welded to the receiving body, for example. 
     A sensor system has one of the receiving devices presented above and one of the rotational speed sensors presented above, wherein the tongue of the rotational speed sensor is or can be coupled to the counter-contour in a rotationally locked manner. For example, with the rotational speed sensor in a received position in the receiving body, the tongue may be coupled to the counter-contour in a rotationally locked manner. Surfaces of the tongue and the counter-contour which prevent rotation can come into contact with each other without play. In the receiving position, the rotational speed sensor can be linearly moved in the receiving body along an axis of the receiving body. The sensor system according to the invention has the advantage that both classic passive (not rotationally locked) and active (rotationally locked) rotational speed sensors can be installed in the same device. 
     A method for rotationally locked positioning of one of the rotational speed sensors presented above on a fixing device has an arranging step. In the arranging step, the tongue of the rotational speed sensor is arranged in or on a counter-contour of a fixing device, wherein in the arranging step the tongue is arranged in such a way that it interacts with the counter-contour, for example it grips in or on the counter-contour to position the rotational speed sensor in a rotationally locked manner. 
     Exemplary embodiments of the approach presented here are explained in more detail in the following description with reference to the figures. 
     In the following description of favorable exemplary embodiments of the present approach, the same or similar reference characters are used for the elements depicted in the various figures with the same or with a similar effect, wherein a repeated description of these elements is dispensed with. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a lateral cross-sectional representation of a rotational speed sensor according to an exemplary embodiment. 
         FIG. 2  shows a rear cross-sectional representation of a rotational speed sensor according to an exemplary embodiment (section A-A of  FIG. 1 ). 
         FIGS. 3 a    and  FIG. 3 b    each show a rear cross-sectional representation of a rotational speed sensor and a fixing device according to an exemplary embodiment. 
         FIGS. 4 to 5  each show a rear cross-sectional representation of a rotational speed sensor and a fixing device according to an exemplary embodiment. 
         FIG. 6  shows a lateral cross-sectional representation of a rotational speed sensor with a fixing device according to an exemplary embodiment. 
         FIG. 7  shows a lateral cross-sectional representation of a sensor system with a receiving device with a fixing device and a rotational speed sensor according to an exemplary embodiment. 
         FIG. 8  shows a lateral cross-sectional representation of a receiving device according to an exemplary embodiment. 
         FIG. 9  shows a frontal cross-sectional representation of a receiving device according to an exemplary embodiment (section B-B of  FIG. 8 ). 
         FIGS. 10 and 11  each show a lateral cross-sectional representation of a sensor system according to an exemplary embodiment. 
         FIG. 12  shows a lateral cross-sectional representation of a receiving device according to an exemplary embodiment. 
         FIG. 13  shows a flow diagram of a method for rotationally locked positioning of a rotational speed sensor on a fixing device according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a lateral representation of a rotational speed sensor  100  according to an exemplary embodiment. 
     The rotational speed sensor  100  has a cylindrical sensor head  105  with a measuring tip  110  and a tongue  115 . The tongue  115  is arranged on an outer diameter  120  of the sensor head  105  and is formed in order to interact with a counter-contour of a fixing device as an anti-rotation lock for the rotational speed sensor  100 , for example to grip in or on such a counter-contour. 
     The rotational speed sensor  100  is configured, for example, to sense a rotational speed of a rotor  125  or a pole wheel. For this purpose, the measuring tip  110 , which forms a free end of the rotational speed sensor  100 , is arranged facing the rotor  125  according to this exemplary embodiment. According to this exemplary embodiment, the rotational speed sensor  100  is formed as an active rotational speed sensor  100 . According to this exemplary embodiment, the rotational speed sensor  100  has a first component  130 , which forms a cylindrical base body of the sensor head  105 . The rotor  125  is positioned opposite the rotational speed sensor  100  and in particular opposite to the measuring tip  110 . The measuring tip  110  is arranged at one end of the rotational speed sensor  100  facing the rotor  125 , here at the end of the first component  130  facing the rotor  125 . Furthermore, the rotational speed sensor  100  has a second component  135  which forms the tongue  115  and a cable outlet  150 . According to this exemplary embodiment, the first component  130  and the second component  135  are connected to each other in a rotationally locked manner and in a form-fitting, force-fitting and/or firmly bonded manner. According to an alternative exemplary embodiment, the tongue  115  is arranged on the first component  130  or the entire rotational speed sensor  100  is formed in one piece. 
     According to this exemplary embodiment, the tongue  115  extends radially away from the sensor head  105 . Here, according to this exemplary embodiment the tongue  115  extends away from a cylindrical section of the second component  135  running towards the base body and/or perpendicular to a cylinder center axis  140  or longitudinal axis of the cylindrical sensor head  105 . According to this exemplary embodiment, the tongue  115  is arranged at an end of the sensor head  105  facing away from the measuring tip  110 . The tongue  115  has a rectangular cross-section. 
     On a side of the outer diameter  120  facing away from the tongue  115 , according to this exemplary embodiment the sensor head  105  has a direction indicator  145 , which is formed for to enable rotationally correct alignment of the sensor  100 . The direction indicator  145  is formed as a small projection over the outer diameter  120  or is let into it, for example. 
     The rotational speed sensor  100  presented here realizes an interface element for the rotationally locked fixing of the active rotational speed sensor  100  due to the tongue  115 . The tongue  115  can also be referred to as an “element for rotationally correct alignment”. With the active rotational speed sensor  100 , positionally correct installation relative to the rotor  125  is necessary, wherein the sensor  100  is movable in a holder along the cylinder center axis  140 , for example by a clamping sleeve, see also  FIGS. 7 to 12 . 
       FIG. 1  shows a section axis A-A to which  FIGS. 2 to 5  relate. 
       FIG. 2  shows a frontal cross-sectional representation of a rotational speed sensor  100  according to an exemplary embodiment. This may be an exemplary embodiment of the rotational speed sensor  100  described on the basis of  FIG. 1 , which is shown sectioned along the axis A-A shown in  FIG. 1 . The rotational speed sensor  100  is shown rotated by 90° to the observer compared to the rotational speed sensor  100  shown in  FIG. 1 . 
     It can be seen in  FIG. 2  that the tongue  115  has two side surfaces  200 , which extend parallel to each other according to this exemplary embodiment. An end surface  205  of the tongue connects the side surfaces  200  to each other and forms an outermost end of the tongue  115 . The end surface  205  is convex shaped according to this exemplary embodiment. According to an alternative exemplary embodiment, the end surface  205  is concave or perpendicularly oriented with respect to the side surfaces  200 .  FIG. 2  also shows key surfaces  210 . 
     Two further side surfaces of the tongue  115 , which are oriented transversely to the side surfaces  200  and connect them to each other, can optionally be used to effect fixing of the rotational speed sensor  100  along the longitudinal axis of the rotational speed sensor  100 . 
       FIG. 3 a    again shows the section plane A-A of a rotational speed sensor  100  and a fixing device  300  according to an exemplary embodiment. This can be the rotational speed sensor  100  described in  FIG. 2 . 
     The fixing device  300  is formed to position the rotational speed sensor  100  in a rotationally locked manner. For this purpose, the fixing device  300  has a counter-contour, which can be coupled to the tongue of the rotational speed sensor  100 . According to this exemplary embodiment, the counter-contour forms at least one counter stop surface for the tongue  115 . According to this exemplary embodiment, the fixing device  300  comprises two fixing elements  305 , each of which forms a counter stop surface for the tongue  115 . The fixing elements  305  are formed in a rod shape and/or extend transversely to an extension direction of the tongue  115  and/or are arranged adjacent to each of the side surfaces  200  or end surfaces  205  of the tongue  115 . The rod-shaped fixing elements  305  according to this exemplary embodiment are cylindrical only by way of example. According to this exemplary embodiment, the tongue  115  is thus arranged between the two fixing elements  305 . The side surfaces  200  of the tongue  115  form stop surfaces for the counter-contours. Alternatively, the fixing elements  305  may have another suitable form. 
     The fixing device  300  can also be referred to as a “fixing element for the rotational correct alignment of a sensor”. According to an alternative exemplary embodiment, the fixing device  300  or at least one or both of the fixing elements  305  is formed as a screw stop, a bolt or a tab or directly as part of the receiving device for the sensor. 
     According to this exemplary embodiment, a further direction indicator  310  is arranged on an installation device for installing the rotational speed sensor  100  in a receiving device for mounting the rotational speed sensor  100 , wherein the further direction indicator  310  allows the alignment of the rotational speed sensor  100 . The receiving device is described in more detail in  FIGS. 7 to 12 . 
       FIG. 3 b    again shows the section plane A-A of a rotational speed sensor  100  and a fixing device  300  according to an exemplary embodiment. This can be the rotational speed sensor  100  described in  FIG. 2 . 
     Here, the tongue end surface  205 , as described based on  FIG. 1 , is formed perpendicularly and extends parallel to a stop surface of the fixing device  300 , which serves as a counter-contour to the rotationally locked fixing. In this example, only a single surface is used for rotational locking. The larger the stop surface  205  with a counter-contour, the smaller the resulting angular error which is allowed by the fixing. 
       FIG. 4  shows a cross-sectional representation A-A from  FIG. 1  of a rotational speed sensor  100  and a fixing device  300  according to an exemplary embodiment. This can be the rotational speed sensor  100  described in  FIG. 2 or 3 , with the difference that the end surface  205  of the tongue  115  has a tongue groove  400 . The fixing device  300  may comprise only one of the fixing elements described in  FIG. 3 , which according to this exemplary embodiment is partially received in the tongue groove  400 . As a counter-contour for the tongue  115 , the fixing element forms a protrusion which engages in the tongue groove  400 . According to this exemplary embodiment, the tongue groove  400  is arranged in the end surface  205  centrally and/or in a semi-circular manner. According to this exemplary embodiment, the tongue groove  400  serves as a stop surface for the counter-contour of the fixing device  300 . 
       FIG. 5  shows a cross-sectional representation A-A from  FIG. 1  of a rotational speed sensor  100  and a fixing device  300  according to an exemplary embodiment. This can be the rotational speed sensor  100  described in  FIG. 2 . According to this exemplary embodiment, the fixing device  300  has a bearing body  500  with a counter-contour in the form of a receiving groove  505 , which is formed to receive the tongue. According to this exemplary embodiment, two mutually facing inner groove surfaces  510  of the receiving groove  505  each form a counter-stop surface for the side surfaces of the tongue arranged in the receiving groove  505 . 
     According to this exemplary embodiment, the bearing body  500  has one or two through holes, here bores  515  for example, for receiving at least one screw or a rod. According to this exemplary embodiment, the two bores  515  according to this exemplary embodiment are arranged one below the other, i.e. one after the other on an extension of a depth of the receiving groove  505 . According to this exemplary embodiment, the bores  515  each extend transversely to the depth of the receiving groove  505  and parallel to the longitudinal axis of the rotational speed sensor  100 . 
     According to an exemplary embodiment, a fastening element is passed through each of the bores  515 , by which the fixing device  300  can be attached, for example, to a fixed machine part, as shown in  FIG. 7 . 
       FIG. 6  shows a lateral cross-sectional representation of a rotational speed sensor  100  with a fixing device  300  according to an exemplary embodiment. This can be the rotational speed sensor  100  and the fixing device  300  described in  FIG. 5 . The fastening elements  615  passed through the bores are two screws according to this exemplary embodiment. Even if the rotational speed sensor  100  is mounted in the fixing device  300  in a rotationally locked manner, it can still be moved in the axial direction, i.e. along its longitudinal axis. 
       FIG. 7  shows a lateral cross-sectional representation of a sensor system  700  with a receiving device  705  with a fixing device  300  and a rotational speed sensor  100  according to an exemplary embodiment. The fixing device  300  can be the fixing device  300  described in  FIG. 6  and the rotational speed sensor  100  can be the rotational speed sensor  100  described in  FIG. 6 . The sensor system  700  comprises the receiving device  705  and the rotational speed sensor  100 . The receiving device  705  again has a receiving body  710 , which is formed to accommodate at least a section of the sensor head  105 , and the fixing device  300 . According to this exemplary embodiment, the receiving body  710  has a cylindrical receiving bore  711  in which the cylindrical base body of the sensor head  105  is at least partially received by a clamping sleeve  720 . The receiving body  710  and the fixing device  300  may be connected to each other in a form-fitting, force-fitting and/or firmly bonded manner. According to this exemplary embodiment, there is a form-fitting and additionally force-fitting connection. For this purpose, the fastening elements  615  of the fixing device  300  implemented as bolts are arranged screwed through the holes in the fixing device  300  into the receiving body  710 . In addition, the fixing device  300  and the receiving body  710  are locked together by a locking device  712 . The locking device  712  comprises suitable interlocking contours, which are formed on mutually opposing surfaces of the fixing device  300  and the receiving body  710 . For example, the fixing device  300  has one or more protrusions and the receiving body  710  has one or more corresponding slots, or vice versa. 
     The rotational speed sensor  100  is arranged to be linearly movable parallel to its longitudinal axis in the cylindrical bore of the receiving body  710  with the help of the clamping sleeve  720 . The clamping sleeve  720  is arranged in a circumferential gap between the sensor head  105  and the wall of the receiving bore  711 . The clamping sleeve  720  may have one or more spring elements, which are supported on the circumferential wall of the receiving bore  711  and which van press against the sensor head  105  to keep the sensor head  105  linearly movable in the receiving bore  711 . 
     In a received position  715  of the rotational speed sensor  100  in the receiving body  710  shown here, the tongue  115  and thus the entire rotational speed sensor  100  is coupled in a rotationally locked manner to the counter-contour of the fixing device  300  formed by the receiving groove  505 . According to this exemplary embodiment, the receiving groove  505  is formed continuously over an entire length of the fixing device  300  in the longitudinal direction of the rotational speed sensor  100 . In this way, the rotational speed sensor  100  can be moved freely in the longitudinal direction. 
     According to this exemplary embodiment, the sensor implemented here as a rotational speed sensor  100  is rotationally fixed by the fixing device  300  in the form of a further component and is installed correctly in the existing receiving body  710  in the form of an axle, which further makes it possible to move the rotational speed sensor  100  in the axial direction. According to this exemplary embodiment, only bores/threads for the fixing device  300  in the form of a fixing plate are applied to the receiving body  710  at an outer wall of the receiving body  710  parallel to the receiving bore  711 . According to an alternative exemplary embodiment, the fixing device  300  is cast in the form of a fixing contour directly on the receiving body  710 . Thus, no further fixing component such as one or more screws is required. 
     According to an exemplary embodiment, the bearing body may be a stamped and bent part. In addition to or as an alternative to the screws shown here and/or the locking device  712 , the fixing device  300  according to an alternative exemplary embodiment comprises at least a tongue and groove joint and/or groove and groove joint and/or a rivet. 
     According to an alternative exemplary embodiment, the fixing device  300  may be one of the fixing devices  300  described on the basis of one of  FIGS. 3 to 5 , which is connected to the receiving body  710  in one piece or in a form-fitting, firmly bonded and/or force-fitting manner. 
       FIG. 8  shows a lateral cross-sectional representation of a receiving device  705  according to an exemplary embodiment. This may be the receiving device  705  described in  FIG. 7 , with the difference that the fixing device  300  is formed as an extension of the receiving device  705 . The fixing device  300  forms a receiving groove  505  as described in  FIG. 7 . According to an alternative exemplary embodiment, the fixing device  300  is formed by two, for example rod-shaped fixing elements  305 , as described on the basis of  FIG. 3 , for example. 
     The receiving body  710  and the fixing device  300  are formed in one piece according to this exemplary embodiment. According to this exemplary embodiment, an external diameter of the receiving body  710  has one or more tabs  800 , which are formed, for example, to mount the receiving device  705  on a truck or trailer. 
     According to this exemplary embodiment, the fixing device  300  in the form of an anti-rotation lock is attached directly to the receiving body  710  in the form of a holder, as is often used in trailers. The fixing device  300  realizes an extension of a receiving body  710  in the form of an installation device with a fixing element for positionally correct installation of the sensor. The receiving body  710  is formed according to this exemplary embodiment as a pipe with welding tabs or screw tabs  800  as a sensor holder on a trailer or a truck, for example. According to an alternative embodiment, the receiving body  710  has a recess and/or a clamping sleeve for guiding the sensor directly in the tube. As a further advantageous exemplary embodiment, the receiving device  705  comprises a device for a stamped bent part for fixing. 
       FIG. 8  also shows a section axis B-B. 
       FIG. 9  shows a frontal cross-sectional representation of a receiving device  705  according to an exemplary embodiment. This may be an embodiment of the receiving device  705  described on the basis of  FIG. 8 , which is shown sectioned along the section axis B-B shown in  FIG. 8 . The section thus runs through the fixing device  300 . 
     The receiving device  705  is shown rotated by 90° to the observer relative to the receiving device  705  shown in  FIG. 8 . It can be seen in  FIG. 9  that two opposing fixing elements  305  are formed by the receiving groove  505 , which according to this exemplary embodiment each have the shape of an annular segment in cross-section by way of example. Two mutually facing inner surfaces of the fixing elements  305  run parallel to each other according to this exemplary embodiment and form groove inner surfaces which serve as stop surfaces for side surfaces of the tongue of the rotational speed sensor  100 . 
       FIG. 10  shows a lateral cross-sectional representation of a sensor system  700  according to an exemplary embodiment. This can be the sensor system  700  described in  FIG. 7 , with the difference that the receiving device  705  corresponds to the receiving device  705  described in  FIG. 8 or 9 . The rotational speed sensor  100  is arranged in the receiving position in the receiving device  705  and is mounted in a rotationally locked manner but linearly movably by the fixing device. 
       FIG. 11  shows a lateral cross-sectional representation of a sensor system  700  according to an exemplary embodiment. This can be the sensor system  700  described in  FIG. 10 . The rotational speed sensor  100  is formed in one piece according to this exemplary embodiment. The fixing device  300  is formed as an extension of the receiving device  705 . 
       FIG. 12  shows a lateral cross-sectional representation of a receiving device  705  according to an exemplary embodiment. This can be the receiving device  705  described in  FIG. 11 . The fixing device  300  can be one of the fixing devices  300  described on the basis of one of  FIGS. 3 to 11 , which is connected to the receiving body in one piece or in a form-fitting, firmly bonded and/or force-fitting manner. 
       FIG. 13  shows a flow diagram of a method  1300  for the rotationally locked positioning of a rotational speed sensor on a fixing device according to an exemplary embodiment. This can be one of the rotational speed sensors described in one of  FIGS. 1 to 12  and one of the fixing devices described in one of  FIGS. 3 to 12 . 
     The method  1300  has an arranging step  1305  in which the tongue of the rotational speed sensor is arranged in or on a counter-contour of a fixing device, wherein in the arranging step  1305  the tongue is arranged in such a way that it interacts with the counter-contour, for example it grips in or on the counter-contour to position the rotational speed sensor in a rotationally locked manner. 
     Optionally, the method  1300  has a providing step  1310  before the arranging step  1305 , wherein the rotational speed sensor and fixing device are provided in the providing step  1310 . 
     If an exemplary embodiment comprises an “and/or” link between a first feature and a second feature, this is to be read in such a way that according to one implementation the exemplary embodiment has both the first feature and the second feature and according to a further implementation the exemplary embodiment has either only the first feature or only the second feature. 
     THE REFERENCE CHARACTER LIST IS AS FOLLOWS 
     
         
           100  Rotational speed sensor 
           105  Sensor head 
           110  Measuring tip 
           115  Tongue 
           120  External diameter 
           125  Rotor 
           130  First component 
           135  Second component 
           140  Cylinder center axis 
           145  Direction indicator 
           150  Cable outlet 
           200  Side surface 
           205  End surface 
           210  Key surface 
           300  Fixing device 
           305  Fixing element 
           310  Further directional indicator 
           400  Tongue groove 
           500  Bearing body 
           505  Receiving groove 
           510  Groove inner surface 
           515  Bores 
           615  Fastening element 
           700  Sensor system 
           705  Receiving device 
           710  Receiving body 
           711  Receiving bore 
           712  Locking device 
           715  Receiving position 
           720  Clamping sleeve 
           800  Tab 
           1300  Method for rotationally locked positioning of a rotational speed sensor on a fixing device 
           1305  Arranging step 
           1310  Providing step