Abstract:
A positioning device includes a housing ( 10 ) and a display unit ( 12 ), in particular a display for graphic representation of measurement information, which display is movable for locating purposes using a handle unit ( 14 ) over a surface of an article being examined. The device has at least one sensor unit ( 20 ) for picking up a first motion parameter. At least one motion measuring direction ( 16, 18 ) extends transversely to the longitudinal direction ( 22 ) of the housing ( 10 ).

Description:
BACKGROUND OF THE INVENTION 
   The invention is a based on a positioning device including a housing and a display unit, preferably a display for graphic representation of measurement information. 
   A handheld positioning device is known that has a chassis with four wheels, of which two wheels are mounted on each long side of the positioning device. The opposite wheels are each connected via an axle extending perpendicular to the longitudinal direction of the positioning device. The positioning device has a display on a top side of its housing and a handle unit, which extends in the longitudinal direction and with which the positioning device can be moved with running surfaces of the wheels over a surface of an item being examined in the direction of its longitudinal direction. 
   For picking up a motion parameter using a sensor unit, the two rigid axles and the sensor unit are mechanically coupled via a toothed belt. 
   SUMMARY OF THE INVENTION 
   The invention is based on a positioning device, having a housing and having a display unit, in particular a display for graphic representation of measurement information, which display is movable for locating purposes using a handle unit over a surface of an article being examined, and having at least one sensor unit for picking up a first motion parameter. 
   It is proposed that at least one motion measuring direction extends transversely to the longitudinal direction of the housing. The positioning device, or the housing, can move with a measurement unit far into a corner in order to locate items, and measurement can be performed up to a distance far into the corner. If the positioning device is movable in two opposed directions during one measurement or locating operation, then the positioning device can be moved into two opposite corners, making it unnecessary to turn the positioning device around. Especially advantageously, a measurement unit for locating items is embodied or disposed essentially symmetrically to a plane that is defined by a center axis of the positioning device and a normal of a top side of the positioning device. Advantageously, accessibility into corners can be attained. 
   If at least one measurement unit is disposed in the housing in the longitudinal direction of the housing in an end region, then the housing with its measurement unit can advantageously be moved closely along a corner. 
   In a further feature of the invention, it is proposed that a transverse direction of the housing is determined essentially by the width of the measurement unit. A positioning device that is especially small in size and can thus get into corners is thus attainable, and in particular a positioning device with an advantageous maximum transverse direction of less than 12 cm can be achieved. 
   It is also proposed that a chassis with at least one roller body, whose axle is passed into the measurement unit, is disposed on the housing. The installation space inside the measurement unit can advantageously be utilized, and additional installation space can be avoided, especially installation space in the transverse direction in front of and behind the measurement unit. 
   If the axle is passed into and through the measurement unit, and if the chassis has at least two roller bodies joined together via the axle in a manner fixed against relative rotation, then straight-ahead travel with high tracking stability can be achieved, especially if the roller bodies are disposed on opposite face ends of the housing. 
   If at least one protrusion for protecting at least one roller body is disposed on an underside of the housing, then when the housing is moved over an edge, the roller body can advantageously be prevented from catching on it and/or becoming damaged. Moreover, if the positioning device is dropped, the roller body and/or the axles are relieved by the protrusion, because when the positioning device strikes a surface below it, the protrusion comes into contact with that surface before plastic deformation of the axle and/or of the roller body can occur. 
   It is also proposed that at least two control elements are disposed on the housing in front of and/or behind a surface to be grasped of the handle unit in terms of the longitudinal direction of the housing. Advantageously, additional installation space for laterally disposed control elements can then be avoided. 
   Especially advantageously, the control elements are disposed inside a front region, pointing in the longitudinal direction, with a radius of 60 mm from a front end of the handle unit. One-hand operation is attainable, in which all the control elements required for a measurement operation are operable. If the control elements are located in a region smaller than 25 mm, then they can be especially conveniently actuated by the user. 
   It is furthermore proposed that the handle unit be embodied symmetrically to a plane that is defined by a longitudinal center axis and by a normal to a top side of the positioning device. Advantageously, via the handle unit, both right-handed and left-handed users can conveniently grasp the positioning device and move it using either the right or the left hand. If the handle unit is mounted at an angle to a center axis of the housing extending in the longitudinal direction, then convenience for certain target groups of users can be enhanced, and if the handle unit is supported pivotably about a vertical axis extending through the center axis, then convenience for all the target groups can be enhanced. 
   Advantageously, the handle unit has a cross-sectional area that tapers in the direction of a top side of the housing and in particular is diamond-shaped. An advantageously ergonomically shaped handle unit is attainable, by way of which the user can move the positioning device over the surface of the item being examined with little fatigue. 
   In a further feature of the invention, it is proposed that not only the first motion parameter but at least also a second motion parameter can be detected with the sensor unit. 
   Advantageously, additional information can be acquired, such as information pertaining to a spacing of the housing from the surface of the item being examined and/or information pertaining to a motion of the housing along a curved path, and so forth. The measurement results can be corrected with the additional information, and measurement errors can advantageously be at least reduced. Moreover, measurement errors, especially errors caused by unintentional change in a motion measuring direction, can be displayed on a display and corrected manually and/or automatically via actuators. In addition, if the sensor unit should fail, with regard to detecting the first motion parameter, an at least partly usable measurement result can be attained with the second motion parameter, especially if the second motion parameter corresponds in terms of type to the first motion parameter. 
   If from the motion parameters detected, a parameter for a rotary motion of the housing about at least one axis can be ascertained, then it is simple to draw a conclusion about an unwanted motion of the housing, especially if the axis extends in the direction of the normal to the surface of the item being examined. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further advantages will become apparent from the ensuing drawing description. In the drawing, one exemplary embodiment of the invention is shown. The drawing, description and claims include numerous characteristics in combination. One skilled in the art will expediently consider the characteristics individually as well and put them together to make useful further combinations. 
     Shown are: 
       FIG. 1 , a positioning device in a top view; 
       FIG. 2 , a section taken along the line II—II in  FIG. 1 ; and 
       FIG. 3 , a detail of an underside of the positioning device of FIG.  1 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  shows a positioning device presented here, with a housing  10  and a chassis  30 . The housing  10  of the positioning device is movable in two preferred, opposed motion measuring directions  16 ,  18 , which extend perpendicular to a longitudinal direction  22  of the housing  10 . On its top side  70 , the housing  10  has a handle unit  14 , formed by a hooplike grip, with a surface  62  to be grasped. The handle unit  14  extends in the longitudinal direction  22  of the housing  10  and is embodied symmetrically to a plane that is defined by a longitudinal center axis  68  and by a normal  82  to the top side  70  of the positioning device (FIG.  1 ). 
   The handle unit  14  has a diamond-shaped cross-sectional area that narrows in the direction of the top side  70  and that with its first end  72 , which points in the longitudinal direction  22  of the housing  10  toward an end region  74  of the housing  10 , merges with the housing  10 , while with its second end  66 , the handle unit  14  opens out at the top side  70  of the housing  10  (FIGS.  1  and  2 ). 
   On its second end  66 , the handle unit  14  has a first control element  54  ( FIG. 1 ) in the longitudinal direction  22  in the direction of an LCD screen  12 , following the surface  62  to be grasped. Following the handle unit  14 , in the longitudinal direction  22  of the housing  10  in the direction of the LCD screen  12 , which is a color screen, but can also be a monochromatic screen, there is a control field  76  with three control elements  56 ,  58 ,  60 ; the control elements  56 ,  58 ,  60  are disposed in a region  64  with a radius of approximately 25 mm from the end  66  of the handle unit  14 . A user can guide the positioning device with one hand using the handle unit  14  and at the same time can operate the control elements  54 ,  56 ,  58  and  60  with his thumb. 
   The handle unit  14  protrudes past the top side  70  of the positioning device and forms a roll bar for protecting the LCD screen  12 . In the longitudinal direction  22  of the housing  10 , in an end region  24 , below the LCD screen  12 , the positioning device has a measurement unit  26 ; a transverse direction  28  of the housing  10  is essentially equivalent to a width of the measurement unit  26 , specifically being approximately 100 mm (FIG.  1 ). The measurement unit  26  is embodied symmetrically to a plane that is defined by the longitudinal center axis  68  and by the normal  82  to the top side  72  of the positioning device. 
   The positioning device has four roller bodies  32 ,  34 ,  36 ,  38 , embodied as wheels, which in the longitudinal direction  22  are disposed on opposite face ends  44 ,  46  in the transverse direction  28  in the outer region (FIG.  1 ). It is also conceivable to equip the positioning device with only three roller bodies; in that case, two roller bodies can be disposed on one face end, while a single roller body is disposed on an opposite face end. The various roller bodies  32 ,  34 ,  36 ,  38  opposite one another in the longitudinal direction  22  are connected to one another in a manner fixed against relative rotation via rigid axles  40 ,  42 , and the rigid axles  40 ,  42  are passed through the measurement unit  26 . 
   On an underside  48  of the housing  10 , for protecting the roller bodies  32 ,  34 ,  36 ,  38 , protrusions  50 ,  52  are formed on; essentially, they take the form of a disklike segment of a circle (FIGS.  2  and  3 ). 
   For picking up motion parameters, the positioning device has a sensor unit  20  with two sensors  78 ,  80 , with which a first and a second motion parameter can be detected (FIG.  3 ). The sensors  78 ,  80  of the sensor unit  20  are formed by optoelectronic components, or more specifically bifurcated light gates. For detecting the motion parameters, each sensor  78 ,  80  is coupled to a respective axle  40 ,  42  of the chassis  30 , so that the first motion parameter can be detected via the first axle  40  and the second motion parameter can be detected via the second axle  42 . The two axles  40 ,  42  are electronically coupled via the sensors  78 ,  80  of the sensor unit. 
   Segment wheels, not shown, are slipped onto the axles  40 ,  42  and move through the bifurcated light gates that form the sensors  78 ,  80 . If per segment wheel, the sensors  78 ,  80  each have two light gates with a suitable offset from one another, then it is advantageously possible via a phase relationship of the two output signals to determine the motion measuring direction  16 ,  18  of the positioning device using the sensor unit  20 . 
   If a user moves the housing  10  over the surface of an item to be examined, the roller bodies  32 ,  34 ,  36 ,  38  of the chassis  30  also roll with their surfaces  84  along the surface of the item being examined. With the roller bodies  32 ,  34 ,  36 ,  38 , the axles  40 ,  42  are rotated, and with the axles  40 ,  42 , the segment wheels are rotated. 
   The motion parameters, or the rotary speeds of the axles  40 ,  42 , detected by the sensors  78 ,  80  are compared in an evaluation unit, not shown in detail, so that from the motion parameters, a conclusion can be drawn as to a parameter for a rotary motion of the housing  10  about an axis  82 , which extends in the direction of the normal to the surface of the item being examined and furthermore forms the normal to the top side  70  of the positioning device. 
   If while the positioning device is being moved over a subject being examined, an object is displayed on the LCD screen  12 , a notch  86  embodied on a face end  46  of the housing  10  indicates the position of the object in the item being examined, relative to the housing  10 . 
   List of Reference Numerals 
   
       
         10  Housing 
         12  Display unit 
         14  Handle unit 
         16  Motion measuring direction 
         18  Motion measuring direction 
         20  Sensor unit 
         22  Longitudinal direction 
         24  End region 
         26  Measurement unit 
         28  Transverse direction 
         30  Chassis 
         32  Roller body 
         34  Roller body 
         36  Roller body 
         38  Roller body 
         40  Axle 
         42  Axle 
         44  Face end 
         46  Face end 
         48  Underside 
         50  Protrusion 
         52  Protrusion 
         54  Control element 
         56  Control element 
         58  Control element 
         60  Control element 
         62  Surface to be grasped 
         64  Region 
         66  End 
         68  Longitudinal center axis 
         70  Top side 
         72  End 
         74  End region 
         78  Sensor 
         80  Sensor 
         82  Axis 
         84  Face 
         86  Notch