Abstract:
The invention concerns a device and a method for determining length, area, and/or volume using a distance measuring device  10  having a transmit unit  18  and a receive unit  20  in one housing, having a keypad  28  for operating the measuring device  10,  and having an integrated computer  22  for evaluating measured data, and a display panel  26  for displaying the measurement results.  
     It is proposed that the display panel  26  of the measuring device  10 —after the operator selects a desired measurement mode by pressing just one button  32  on the keypad  28 —uses an icon-based graphic display to indicate which of the individual measurements required to determine the desired measurement variable has yet to be carried out.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention concerns a method and a device for determining length, area, and volume using a distance measuring device.  
           [0002]    A method and a device for measuring area and volume was made known in DE 198 48 628 A1, which said device is based on the fact that, from a central point in the space to be measured, all spacial and surface corner points to be detected are pointed at and acted upon by a laser beam. The 3D values of the corner points are determined by the reflected laser beam based on the distance and the associated angles, and a true-to-scale drawing is created. The device disclosed in DE 198 48 628 A1 includes a laser distance measuring device comprising a laser transmitter and a laser receiver that is attached to a stand via a tilting and rotating device for positioning and for measuring angles. The device disclosed in DE 198 48 628 A1 also includes a telescopic sight and an electronic evaluation unit for capturing and transmitting data on angles and distances, and a computer connected therewith.  
           [0003]    The method disclosed in DE 198 48 628 A1 is extremely expensive and requires a relatively long preparation period on the part of the operator, since a reference coordinate system, among other things, must be determined in advance of every measurement. Moreover, an additional external computer is needed for the method presented that has a further negative impact on the costs and the user friendliness of this measuring system.  
           [0004]    A laser distance measuring device (“DLE 30 Laser plus”) is made known in the catalog entitled “Gewerbliche Elektrowerkzeuge: Bosch Programm 2000/2001” from Robert Bosch GmbH, D-70442, Stuftgart, Germany, with which said device length, area and volume can be measured. This device has a multi-line display panel in which, when a measurement mode is selected (for measuring either length, area, or volume), the type of measurement and the lengths to be measured are presented using icons.  
           [0005]    Moreover, the “DLE 30 Laser plus” laser distance measuring device has a keypad, each button of which is associated with a measurement mode. By pressing one of these buttons, the measurement mode associated with this button is selected, and the desired measurement variable can be determined by starting the measuring procedure.  
           [0006]    This device has the disadvantage that the measurement signal used is a laser beam that absolutely must not strike the eye of the operator or the eyes of anyone else present in the surroundings where the measurement takes place, because this can cause irreversible damage to the retina. This measuring device is also relatively large and heavy for a handheld measuring device.  
           [0007]    The invention is therefore based on the object of creating a method and a device for calculating length, area and volume that provides relatively accurate measured results and that the operator finds easy and intuitive to learn and that are safe to operate.  
           [0008]    This object is attained, according to the invention, by the features of the independent claims. Advantageous embodiments and further developments of the invention are demonstrated in the dependent claims.  
         ADVANTAGES OF THE INVENTION  
         [0009]    The method according to the invention and the device operating according to this method for measuring length, area, and volume have the advantage that the desired measurement mode can be selected and changed using just one button on the keypad.  
           [0010]    As a result, the keypad on the measuring device is clearly arranged, which makes the device easy to understand and operate.  
           [0011]    A measurement mode selected once via the unequivocal measurement mode button on the device is shown in a schematic, graphic presentation in the display panel and can therefore be easily monitored by the operator.  
           [0012]    With the method according to the invention, the operator—after selecting the desired measurement mode—advantageously need only carry out individual length measurements that an integrated computer in the measuring device evaluates after the required measurements are completed and automatically determines the desired area or volume dimensions and presents them immediately in the display panel of the measuring device.  
           [0013]    The display panel of the measuring device according to the invention displays the most recently measured value along with the length, area or volume dimension determined by the computer.  
           [0014]    The ease of use and intuitive understandability of the measuring device are supported by the fact that, by means of the method according to the invention, the operator is instructed via the display panel as to which path measurements are still required in order to determine an area or volume dimension. The operator is requested via an icon-based, graphic presentation in the display panel of the measuring device to perform the length measurements required. This results in a nearly self-explaining measuring device. No training or studying of extensive operating manuals are required with the measuring device according to the invention.  
           [0015]    An aspect that also contributes advantageously to the safe and simple use of the measuring device is the fact that the operator is informed via the display panel of the device if the measuring procedure is still underway. The completion of each individual measurement is indicated by means of an additional signal, such as an acoustic signal, for example.  
           [0016]    In terms of the ease of use of the measuring device, it is also advantageous that the measurement direction can be indicated by means of an optical signal output with the actual measurement signal. If an ultrasonic distance measuring device is used, the reference point pointed at with the device can be checked.  
           [0017]    An electronic memory integrated in the measuring device makes it possible to advantageously store measured values, to add different measured values, and to recall stored measured values and present them in the display panel of the measuring device.  
           [0018]    The computer integrated in the measuring device, and its electronic memory can be advantageously operated via buttons on the operating panel of the measuring device. 
       
    
    
     SUMMARY OF THE DRAWINGS  
       [0019]    An exemplary embodiment of the invention is presented in the drawing and it is explained in greater detail in the subsequent description.  
         [0020]    [0020]FIG. 1 shows a perspective illustration of a device, according to the invention, for determining length, area, and volume.  
         [0021]    [0021]FIG. 2 shows a simplified flow diagram of the method, according to the invention, for determining length, area, and volume.  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    The handheld device according to the invention and shown in a perspective view in FIG. 1 for determining length, area, and volume—referred to hereinafter as the measuring device  10 —has a housing  12  that, in the exemplary embodiment shown, is composed of a top half-shell  14  and a bottom half-shell  16 . Integrated in the housing  12  and therefore not visible in FIG. 1 are a transmit unit  18  and a receive unit  20  for the measurement signal, as well as an internal computer  22  with associated memory  24 .  
         [0023]    The housing  12  has a display panel  26  and a keypad  28 . In the present exemplary embodiment of the measuring device  10  according to the invention, the keypad  28  has a button  30  for turning the measuring device on and off, a button  32  for selecting the measurement mode, and a measurement button  34  for starting each measurement procedure. Moreover, in the present exemplary embodiment, the keypad  28  has a button  36  for recalling the contents of a memory  24  of the computer  22  located inside the measuring device, and a button  38  for automatically adding the most recent measured value to the existing contents of the memory  24 . The current measured value shown in the display panel  26  can be cleared by pressing a button  40  on the keypad  28  one time. Pressing the button  40  twice clears the contents of the memory  24  of the internal computer  22 .  
         [0024]    Located on the front side  42  of the housing  12  is an opening  44  for the measurement signal to leave the housing  12  and for the reflected signal to enter the housing  12 . In the exemplary embodiment presented here, the measured signal used is ultrasound. In principle, however, the invention is not limited to the use of ultrasound as a measurement signal. Waves of other frequencies can also be used for measuring distance.  
         [0025]    Located on the front side  42  of the measuring device  12  is a second opening  46 , out of which an optical signal that is parallel to the measurement signal can exit. Using this optical signal, it is possible to accurately determine the reference point aimed at when performing a measurement.  
         [0026]    The back side  48  of the housing  12  of the measuring device  10  according to the invention functions as a reference plane for determining length.  
         [0027]    The flow diagram shown in FIG. 2 describes the sequence and application of a plurality of measurement functions that are possible with the device according to the invention. The device has various measurement functions that can be selected by repeatedly pressing the measurement mode button. The sequence that occurs when the measurement mode button is pressed is as follows: measure length, measure area, measure volume.  
         [0028]    The method according to the invention for determining length, area and volume will be described hereinbelow with reference to the individual procedural steps (S) of an exemplary embodiment.  
         [0029]    After the device is turned on (S 1 ) using the ON/OFF button  30 , the measuring device  10  automatically enters the “measure length” mode. A blinking line appears in the display panel  26  as a request to the operator to perform a length measurement. The operator must now decide (S 2 ) if he wants to measure length or perform another measurement function.  
         [0030]    If the operator wants to measure length, he can start the length measurement directly by pressing measurement button  34  on the keypad  28  (S 3 ). Before doing so, the operator must position the measuring device  10 , i.e., he must place the back side  48  on a point at which the measurement is to begin. The operator positions the measuring device  10  toward the target area at a right angle, then presses measurement button  34  to start the measurement procedure.  
         [0031]    During the measurement procedure, a line icon extending from right to left in the display panel  26  indicates to the operator that a measurement is being carried out (S 4 ). An additional acoustic signal sounds to indicate that each individual measurement has been completed, and the actual measured value for the length measurement appears immediately in the lower right-hand corner of the display panel  26  of the measuring device  10  (S 5 ).  
         [0032]    If the length of a path cannot be determined internally in the device, the acoustic signal does not sound, and a display appears in the display panel  26  to indicate that the measurement was unsuccessful. The measuring device is then ready to perform further measurements.  
         [0033]    If the operator does not want to measure length, but he does want to measure area or volume, he must press mode button  32  (S 6 ) after the measuring device is turned on (S 1 ). After the mode button  32  is pressed once (S 6 ), a square icon appears in the lower left-hand corner of the display panel  26  of the device  10  that indicates that the measuring device  10  is now in the “measure area” mode. The operator must now decide (S 7 ) if he wants to measure area or volume.  
         [0034]    If the operator wants to measure volume, he presses mode button  32  one more time (S 8 ). A cube icon appears in the display panel  26  of the measuring device  10  to inform the operator that the device is now in the “measure volume” mode.  
         [0035]    If the operator wants to measure area, the measuring device  10  is ready to measure area after step S 6  is performed.  
         [0036]    If the measuring device  10  has already been turned on and is not in the “measure area” mode, the operator must press mode button  32  repeatedly until the square icon appears in the lower left-hand corner of the display panel  26 .  
         [0037]    A first side of the square icon blinks in the display panel  26  of the measuring device  10  (S 9 ) as a request to the operator of the measuring device  10  to perform a first length measurement in order to determine the desired area.  
         [0038]    The operator presses measurement button  34  (S 10 ) to start the measurement procedure. Again, an acoustic signal is emitted by the device to indicate that the procedure has been completed.  
         [0039]    The length value determined for the first side of the desired area appears in the display panel  26  of the measuring device  10 . The corresponding side of the square icon stops blinking in the display  26  (S 11 ).  
         [0040]    A second side of the square blinks in the display  26  of the measuring device  10  (S 12 ) as a request to the operator to perform a second length measurement that is orthogonal to the first measurement in order to determine the desired area.  
         [0041]    When measurement button  34  is pressed again (S 13 ), the second path length required to calculate area is obtained. The most recently determined path length and the surface area determined by the internal computer  22  in the measuring device  10  based on the two previous length measurements is displayed in the display panel  26  of the measuring device  10  (S 14 ).  
         [0042]    If the measuring device  10  is in the “measure volume” mode (S 8 ), this is indicated by means of a cube icon in the lower left-hand corner of the display panel  26 . If the device  10  has already been turned on and is not in the “measure volume” mode, the operator must press mode button  32  repeatedly until the cube icon appears in the lower left-hand corner of the display panel  26  of the measuring device  10 .  
         [0043]    A first side of the cube icon blinks as a request to the operator to measure the length of a first path of the desired volume (S 16 ).  
         [0044]    The operator presses measurement button  34  (S 17 ) to determine this first length and display it in the display panel  26  of the measuring device  10 . The first side that was blinking previously stops blinking (S 18 ).  
         [0045]    A second side of the cube now starts blinking as a request to the operator to measure a second orthogonal path to determine volume (S 19 ). The operator presses measurement button  34  (S 20 ) to determine this second path length.  
         [0046]    When the measurement procedure is over, the display  26  of the measuring device  10  displays the most recently measured path length together with a surface area determined based on the last two path measurements. The second line of the cube icon that blinks in the display panel  26  of the measuring device  10  during the measurement now stops blinking (S 21 ).  
         [0047]    A third line now blinks in the display panel  26  of the measuring device  10  as a request to the operator to measure a third line that is orthogonal to the two previously measured lines in order to determine the desired volume (S 22 ).  
         [0048]    The operator presses measurement button  34  (S 23 ) to determine the third required path length. This third path length is presented along with the volume calculated by the internal computer  22  of the measuring device  10  based on the three most recent length measurements in the display panel  26  of the measuring device  10  (S 24 ).  
         [0049]    In the case of the method according to the invention, the measurement mode can be changed by repeatedly pressing the measurement mode button  32  (S 25 ). The currently selected measurement mode is indicated in each case by means of the corresponding icon for a line (for length measurements), a square (for area measurements) or a cube (for volume measurements) in the lower right-hand corner of the display panel  26  of the measuring device  10 .  
         [0050]    Reference Numerals  
                                         Reference Numerals                                10   Measuring device       11       12   Housing       13       14   Upper half-shell       15       16   Lower half-shell       17       18   Transmit unit       19       20   Receive unit       21       22   Internal computer       23       24   Computer memory       25       26   Display panel       27       28   Keypad       29       30   ON/OFF button       31       32   Measurement mode selection button       33       34   Measurement button       35       36   Memory recall button       37       38   Memory input button       39       40   “Clear” button       41       42   Front side of the housing       43       44   Opening       45       46   Opening       47       48   Back side       49       S1   Power On       S2   Measure length?: Yes or No       S3   Start measurement       S4   Actively measuring       S5   Results display: length measurement       S6   Press measurement mode selection button       S7   Determine area?: Yes or No       S8   Press measurement mode selection button       S9   Request first measurement for determining area       S10   First measurement for determining area       S11   Display the first length value for determining area       S12   Request second measurement for determining area       S13   Second measurement for determining area       S14   Display the second length value and the area dimensions       S15   Measure volume? Yes or No       S16   Request first length measurement for determining volume       S17   First length measurement for determining volume       S18   Display the first length measurement for determining volume       S19   Request the second measurement for determining volume       S20   Second length measurement for determining volume       S21   Display the second length value and the area dimensions       S22   Request the third length measurement for determining volume       S23   Third length measurement for determining volume       S24   Display the third length value and the volume dimensions       S25   Press the measurement mode selection button