Abstract:
The invention relates to a measuring device, especially for a machine tool and/or a manual measuring device, comprising a measuring unit ( 12   a - d ) that is adapted to measure and an external signal recognition unit ( 14   a - d ). The invention is characterized in that the external signal recognition unit ( 14   a - d ) is adapted to recognize an external signal during and/or prior to a measurement of the measuring unit ( 12   a - d ).

Description:
This application is a National Stage Application of PCT/EP2008/059870, filed 28 Jul. 2008, which claims benefit of Serial No. 10 2007 046 645.7, filed 28 Sep. 2007 in Germany and which applications are incorporated herein by reference. To the extent appropriate, a claim of priority is made to each of the above disclosed applications. 
     TECHNICAL FIELD 
     A measuring device for a machine tool and/or a manual measuring device is already known. The measuring device has a measuring unit that is adapted to measure and an external signal unit. 
     SUMMARY 
     The invention relates to a measuring device, especially for a machine tool and/or a manual measuring device, comprising a measuring unit that is adapted to measure and an external signal recognition unit. 
     The invention is characterized in that the external signal recognition unit is adapted to recognize an external signal during and/or prior to a measurement of the measuring unit. In this connection, equipped, designed and/or programmed should be understood by the term “adapted”. By means of the configuration of the invention, an advantageous protection of an external signal of an active service, as for example an air traffic control, a UMTS transmitter etc., can be protected from a disturbance by the measuring unit and/or components of the measuring unit, especially a sensor element and/or a receiving element, can be at least partially protected from a disturbance, respectively from the external signal and/or an overload. A frequency range of the external signal recognition unit to be monitored advantageously corresponds to a measuring frequency, respectively a measuring spectrum, of the measuring unit. A measuring frequency, respectively a measuring spectrum, can be changed to a frequency range by means of the measuring unit, which is omitted from an external signal frequency, respectively an external signal spectrum, when an external signal is present. The measuring unit preferably has an ultra wideband unit, which is adapted to perform ultra wide band measurements, the ultra wide band unit transmitting and/or detecting an ultra wide band signal. In this case, an electromagnetic signal, which has a useful frequency range with a middle frequency in the frequency range of 1 GHz to 15 GHz and a frequency band width of at least 500 MHz, should particularly be understood by the term “ultra wide band signal (or UWB signal)”. 
     The invention is furthermore characterized in that the external signal unit has at least one pulse signal detection unit, which is adapted to detect an external pulse signal, whereby a targeted search for, respectively detection of, in particular periodic, pulsed external signals, as, for example, signals from an air traffic control, can be achieved and in so doing a higher safety standard for services with pulsed signals can be achieved. In this context, a periodic, pulsed external signal, whose cycle duration can be up to twelve seconds, should be understood by the term “external pulse signal”. The external pulse signal is preferably formed from a radar signal. The pulse signal detection unit is preferably is implemented using a diode circuit, such as, for example, a Schottky diode circuit and/or a tunnel-diode circuit. 
     If the measuring unit furthermore has at least one sensor receiver, which is at least partially integral with the pulse signal detection unit, additional components, installation space, assembly work and costs can be saved. In this connection, particularly one-piece should be understood by the term “integral”, i.e. manufactured from one casting or as a single component, in particular configured as an integrated component. A detector element for detecting a measurement signal should thereby be understood by the term “sensor receiver”. 
     The invention is furthermore characterized in that the external signal recognition unit has at least one continuous signal detection unit, which is adapted to detect continuous external signals, whereby a detection of continuous external signals, which is independent of a measuring signal, respectively of external pulse signals, can be achieved. Especially a continually transmitted external signal, as, for example, a UMTS signal, should thereby be understood by the term “continuous external signal”. The continuous signal detection unit preferably has a wide band receiver, which ascertains a received power over a preset frequency range. 
     A particularly space saving arrangement of the measuring unit and at least partially of the external signal recognition unit can advantageously be achieved on a semiconductor chip if the measuring unit has at least one sensor receiver, which at least is configured partially integral with the continuous signal detection unit. 
     In a further configuration of the invention, said invention is characterized in that the external signal recognition unit has at least one antenna element, which is adapted to receive the external signal, whereby a reception of the external signal independent of the measuring unit can be advantageously achieved and thus an undesirable weakening of a received signal, as for example as a result of a signal splitting, is prevented. 
     The invention is furthermore characterized in that the pulse signal detection unit and/or the continuous signal detection unit have (has) the antenna element, whereby a sensitivity of the antenna element can advantageously be adapted to an external signal. 
     Additional components, installation space, assembly work and costs can advantageously be saved if the measuring unit has an antenna unit for receiving and/or transmitting a measurement signal, which has at least partially the antenna element that is adapted to receive the external signal. In so doing, the antenna unit can comprise a montostatic or a bistatic measuring system. 
     The measuring device advantageously has a signal extraction unit, which is adapted to split a received signal of the antenna unit, whereby an advantageous forwarding of the received signal to various detectors, especially a pulse signal detector and/or a continuous signal detector, and/or sensors of the measuring unit can be achieved. The signal extraction unit is thereby preferably formed from a directional coupler and a signal splitter, such as, for example, a Wilkenson power splitter etc. 
     If the signal extraction unit furthermore has at least one switching element, a permanent weakening of a measurement signal can thereby be advantageously avoided by a received signal being split for only a short time within a measuring period or being switched to an additional detector. The switching element is preferably adapted to split or redirect a received signal between the measuring unit and the continuous signal detection unit. 
     The invention is characterized in an advantageous modification thereto in that the measuring device has a signal processing unit, which is adapted to set an operating mode of the measuring unit when an external signal is present, whereby a protection of an active service, for example an air traffic control, and/or the measuring unit can be achieved. The operating mode can thereby be adapted to reduce a power output of at least a part of a measuring spectrum of the measuring unit or can be configured from a cut-out mode. The cut-out mode is preferably adapted to automatically cut-out the measuring unit when an external signal is present. 
     If provision is additionally made for the operating mode to change at least one measuring frequency of the measuring unit, a measuring operation can thereby be advantageously maintained when an external signal is present. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Additional advantages result from the following description of the drawing. Embodiments of the invention are depicted in the drawing. The drawing, the description and the claims contain numerous characteristics in combination. The specialist will also advantageously consider the characteristics individually and arrange them in additional meaningful combinations. 
       The following are shown: 
         FIG. 1  is a schematic configuration of a measuring device, 
         FIG. 2  is an alternative configuration of the measuring device with separate detectors in a schematic depiction, 
         FIG. 3  is an alternative configuration of the measuring device with autonomous detectors in a schematic depiction and 
         FIG. 4  is an alternative configuration of the measuring device having integrally configured detectors in a schematic depiction. 
     
    
    
     DETAILED DESCRIPTION 
     A measuring device  10   a , which is formed from an ultra wide band measuring device and has a measuring unit  12   a  and a external signal recognition unit  14   a , for a machine tool and/or a manual measuring device is depicted in  FIG. 1 . The measuring unit  12   a  has an ultra wide band unit  16   a  with a sensor receiver  22   a , which is formed from an ultra wide band sensor receiver, and an ultra wide band sensor transmitter  38   a . In addition, the measuring unit  12   a  has an antenna unit  30   a , which is adapted to receive an ultra wide band radar signal. The antenna unit  30   a  has an antenna element  24   a  of the external signal recognition unit  14   a , which besides being adapted to transmit and receive an ultra wide band measuring signal of the ultra wide band unit  16   a  is adapted to receive an external signal of the external signal recognition unit  14   a  during and/or prior to a measurement of the measuring unit  14   a . The receive signal of the antenna element  24   a  is directed to a signal extraction unit  32   a , which is adapted to split the receive signal received by the antenna unit  30   a . A first part of the receive signal is directed to the ultra wide band unit  16   a  of the measuring unit  12   a , a second part of the receive signal is directed to the external signal recognition unit  14   a.    
     The external signal recognition unit  14   a  has a pulse signal detector  18   a  and a continuous signal detector  20   a , which are integrally configured with each other. The continuous signal detector  20   a  and the pulse signal detector  18   a  are thereby selective in a frequency range, which is substantially equal to a frequency range of the measuring unit  12   a.    
     Detected, respectively evaluated, data of the external signal recognition unit  14   a  and the measuring unit  12   a  are forwarded to a signal processing unit  36   a , a transport of data and/or signals occurring within the measuring device  10   a  by means of an unspecified data bus. Instead of a data bus, it is in principle however also conceivable to allow for a cable-free, respectively wireless, exchange of data and/or signals and/or an exchange by means of a data cable. 
     During the operation of the measuring device  10   a , said device  10   a  is activated by an operator via an undepicted control element. After that, receive signals, which are directed via the signal extraction unit  32   a  to the external signal recognition unit  14   a , are received by means of the antenna unit  30   a . In order to start a first measurement using the measuring unit  12   a , a search is initially made for a continuous external signal within the response signal with the aid of the external signal recognition unit  14   a , respectively with the aid of the continuous signal recognition unit  20   a , within a time window of approximately 500 ms. An evaluation of the data occurs within the continuous signal detection unit  20   a , the continuous signal detection unit  20   a  having its own processor for this purpose and an evaluated parameter being forwarded to the signal processing unit  36   a . It is in principle however also conceivable for an evaluation  30   a  of the data to occur in the signal processing unit  36   a  and for the continuous signal detection unit  20   a  to forward the data of the antenna unit  30   a  merely to the signal processing unit  36   a . The evaluated parameter can be transmitted to the signal processing unit  36   a  in the form of a digital or an analog parameter. 
     A continuous external signal in the continuous signal detection unit  20   a  is present if a signal is greater than a defined threshold value. If an external signal is not present in the continuous signal detection unit  20   a , respectively the corresponding parameter in the signal processing unit  35   a , the measuring unit  12   a  of the signal processing unit  36   a  is activated and a first measurement can be started. In so doing, a measuring signal with a measuring spectrum from the ultra wide band sensor transmitter  38   a  of the ultra wide band unit  16   a  is directed to the signal extraction unit  32   a  and from here is directed further to the antenna unit  30   a , where said signal is emitted. The measuring signal is reflected off a measuring object and is received by the antenna unit  30   a  and directed via the signal extraction unit  32   a  to the sensor receiver  22   a  and evaluated there. 
     The signal processing unit  36   a  activates the pulse signal detection unit  18   a  simultaneously to the first measurement by the measuring unit  12   a , and said pulse signal detection unit  18   a  begins with a measurement of an external pulse signal. For this purpose, the receive signal, which was directed from the signal extraction unit  32   a  to the pulse signal detection unit  18   a  is evaluated by a processor of the pulse signal detection unit  18   a . An external pulse signal is present if a signal is greater than a threshold value and this threshold value was consecutively exceeded by a plurality of signals, as, for example, five signals. If the pulse repetition frequency lies at approximately 700 Hz, as for example in the range of the air traffic control, the five signals, respectively pulses, for example, have to be detected within 7.2 ms. If the number of detected pulses is under five, an external pulse signal is not present. The pulse signal detection unit  18   a  ascertains a parameter from the detected pulses and forwards this to the signal processing unit  36   a.    
     When the external pulse signal and/or the continuous external signal are (is) present, a change in the operating mode of the ultra wide band unit  16   a  occurs via the signal processing unit  32   a . This operating mode is formed from a cut-out mode, which leads to an automatic cut-out of the ultra wide band sensor transmitter  38   a  of the ultra wide band unit  16   a  when an external signal is present. As an alternative to this, the operating mode could also lead to a change in the measuring frequency, respectively in the measuring spectrum, of the ultra wide band unit  16   a  and/or to a reduction in power of the ultra wide band unit  16   a  so that interferences between the external signal and the measuring signal can be ruled out or at least reduced. The ultra wide band transmitter  38   a , respectively the measuring unit  12   a , remains switched-off in the cut-out mode initially for a cycle duration of at least 12 seconds. The cycle duration corresponds thereby to a cycle duration of a radar signal of the air traffic control. It is in principle also conceivable for the cycle duration for the external pulse signal detection to be adapted to additional interfering signals, respectively interfering sources. If a renewed measurement of an external pulse signal occurs after a cycle, the ultra wide band unit  16   a  remains switched-off for at least one additional cycle duration. If no external pulse signal is detected after a cycle, the ultra wide band unit  16   a  is automatically switched on again, provided a continuous external signal is not present. In so doing, a measuring operation by the measuring unit  12   a  is restored. 
     Beside the recognition, respectively detection, of an external pulse signal, the detection of a continuous external signal continues to occur by means of the continuous signal detection unit  20   a . A measuring operation of the measuring unit  12   a  is possible only if neither an external pulse signal nor a continuous external signal is present. If the measuring unit  12   a  additionally has an optical output unit, as, for example, a display, a current measuring status and/or external signal recognition status can be displayed for the operator of the measuring device  10   a . Furthermore, it is also conceivable for special filters to be arranged upstream of the pulse signal detection unit  18   a  and/or the continuous signal detection unit  20   a  so that only special external signals can be filtered out, respectively recognized. 
     Alternative embodiments are depicted in  FIGS. 2 to 4 . Substantially unchanged components, characteristics and functions are basically labeled with the same reference numerals. In order to distinguish between the embodiments, the letters a to d are, however, added to the reference numerals of the embodiments. The following description limits itself substantially to the differences to the embodiment in  FIG. 1 . In so doing, reference is made to the description of the embodiment in  FIG. 1  with regard to components, characteristics and functions that remain unchanged. 
     An alternative measuring device  10   b  is schematically depicted in  FIG. 2 . The measuring device  10   b  has a measuring unit  12   b  and an external signal recognition unit  14   b . The external signal recognition unit  14   b  has a continuous signal detection unit  20   b  and an external signal detection unit  18   b , which are configured separate from one another. A receive signal of an antenna element  24   b  of an antenna unit  30   b  is directed to a signal extraction unit  32   b  and split there. A first part of the receive signal is directed to the pulse signal detection unit  18   b , a second part of the response signal to a switching element  34   b  of the signal extraction unit  32   b . The receive signal is directed from the switching element  34   b  further to the continuous signal detection unit  20   b , respectively to the measuring unit  12   b . It is sufficient for recognizing an external signal if the receive signal is directed to the continuous signal recognition unit  20   b  by means of the switching element  32   b  within a cycle duration for recognizing an external signal, for example twelve seconds, in a small time window, for example several hundred milliseconds. The receive signal is directed to the measuring unit  12   b , respectively to an ultra wide band unit  16   b  for the remainder of the cycle duration so that a weakening, respectively a damping, of a measuring signal is prevented as much as possible. A detection of continuous external signals and external pulse signals by the external signal recognition unit  14   b  and a measurement with the aid of the measuring unit  12   b  occur analogous to the description regarding  FIG. 1 . 
     An alternative measuring device  10   c  is schematically depicted in  FIG. 3 . The measuring device  10   c  has a measuring unit  12   c  and an external signal recognition unit  14   c . The external signal recognition unit  14   c  has a pulse signal detection unit  18   c  and a continuous signal detection unit  20   c , which are configured separate from one another. The pulse signal detection unit  18   c  has an antenna element  26   c , which is configured separate from an antenna element  28   c  of the continuous signal detection unit  20   c . In addition, the two antenna elements  26   c ,  28   c  are configured separate from an antenna unit  30   c  of the measuring unit  12   c . A detection of continuous external signals and external pulse signals by the external signal recognition unit  14   c  and a measurement with the aid of the measuring unit  12   c  occur analogous to the description regarding  FIG. 1 . It is in principle also conceivable in a further configuration of the invention for the antenna element  26   c  of the pulse signal detection unit  18   c  and the antenna element  28   c  of the continuous signal detection unit  20   c  to be integrally configured with each other so that both external signals, respectively both external signal types, can be received by means of one antenna element  26   c ,  28   c.    
     An alternative measuring device  10   d  is schematically depicted in  FIG. 4 . The measuring device  10   d  has a measuring unit  12   d  and an external signal recognition unit  14   d , which are integrally configured with each other. A sensor receiver  22   d  of an ultra wide band unit  16   d  of the measuring unit  12   d  is thereby a continuous signal detection unit  20   d  and is configured as a pulse signal detection unit  18   d . In so doing, the ultra wide band unit  16   d , respectively the sensor receiver  22   d , is adapted to detect a measuring spectrum, a continuous external signal and an external pulse signal. In an additional configuration of the invention, it is also furthermore conceivable for the sensor receiver  22   d  of the ultra wide band unit  16   d  to be integrally configured with only the continuous signal recognition unit  20   d  or the pulse signal recognition unit  18   d . A detection of continuous external signals and external pulse signals by the external signal recognition unit  14   d  and a measurement with the aid of the measuring unit  12   d  occur analogous to the description regarding  FIGS. 1 and 2 .