Abstract:
A compact monitoring device for monitoring the state of rotation of a disk cutter of a shield tunnel boring machine is integrated into a clamping element for fastening the disk cutter. A sensor module of the monitoring device is arranged in close proximity to the disk cutter but without touching so that a state of rotation of the disk cutter generated by transmitters mounted in the disk cutter is reliably ensured even under the rough environmental conditions prevailing in shield tunnel boring.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a U.S. National Phase Patent Application based on International Application No. PCT/DE2012/000914 filed Sep. 14, 2012, the entire disclosure of which is hereby explicitly incorporated by reference herein. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a device for monitoring the state of rotation of a disk cutter of a shield tunnel boring machine. 
     The invention furthermore relates to a disk cutter arrangement having a device of this type. 
     2. Description of the Related Art 
     A device according to the definition of the species and a disk cutter arrangement equipped with a device according to the definition of the species for a shield tunnel boring machine are known from WO 2009/155110 A2. The device known from the prior art has a base plate and a housing cover of a wedge-shaped design which is manufactured from a chamfered metal sheet. A number of modules, which have an acceleration sensor, a temperature sensor and a magnetic field sensor, are situated in a free end section of the housing cover which projects over the base plate in a retaining space which is thus open on one side. The base plate is situated to the side of a clamping screw shaft of a clamping screw belonging to a clamping unit for fixing a disk cutter axis. A connecting plate, through which the clamping screw shaft extends, is mounted on the base plate at right angles, thereby fastening the housing. The modules accommodated in the housing are connected via a wireless connection to a receiver, by means of which the measured values recorded by the sensors may be processed for monitoring the state of rotation of the disk cutter, whose axis adjoins the free end of the housing cover. 
     SUMMARY OF THE INVENTION 
     The present invention provides a device which has a very stable structure and is thus able to withstand the extremely harsh environmental conditions of a shield tunnel boring machine. 
     The present invention further provides a disk cutter arrangement having a device of this type, which maintains a high reliability in monitoring the state of rotation of a disk cutter. 
     The modules are well protected against damage due to the fact that the retaining space in the device according to the invention is closed on all sides. By designing the housing with a housing block which has a shaft channel accommodating the clamping screw shaft, the housing has a very stable connection to the clamping unit. 
     In one form thereof, the present invention provides a device for monitoring the state of rotation of a disk cutter of a shield tunnel boring machine, including a housing which has at least one retaining space for accommodating modules and is configured for mounting on a clamping unit designed for fastening a disk cutter axis of the disk cutter, characterized in that the or each retaining space is closed on all sides, and the housing has a housing block having the or each retaining space, the housing block being provided with an elongated bushing base as part of the fastening unit, which has a shaft channel extending in the longitudinal direction of the bushing base for accommodating a clamping screw shaft of the clamping unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above mentioned and other features and objects of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  shows a schematic view of a shield tunnel boring machine having a boring head which has a number of disk cutter arrangements provided with disk cutters, and which has a control station; 
         FIG. 2  shows a perspective view of an exemplary embodiment of a disk cutter arrangement, which has a disk cutter housing in which is situated a disk cutter which is fixed by clamping screws; 
         FIG. 3  shows a perspective view of the exemplary embodiment according to  FIG. 2 , in which the disk cutter housing is removed, with a view, in particular, of clamping wedges and clamping blocks connected to the clamping screw, as well as an exemplary embodiment of a device according to the invention, which is situated between a clamping wedge and a clamping block; 
         FIG. 4  shows an enlarged perspective view of the arrangement of the device according to  FIG. 3 ; 
         FIG. 5  shows a perspective exploded view of the arrangement according to  FIG. 4 ; and 
         FIG. 6  shows a block diagram of the essential modules as well as other components for wireless monitoring of the state of rotation of a disk cutter. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. Although the exemplifications set out herein illustrate embodiments of the invention, in several forms, the embodiments disclosed below are not intended to be exhaustive or to be construed as limiting the scope of the invention to the precise forms disclosed. 
     DETAILED DESCRIPTION 
       FIG. 1  shows a clear side view of a shield tunnel boring machine  1 , which has a rotatable boring head  3  on the side facing an excavation face  2 . Boring head  3  is fitted with a number of disk cutter arrangements  4 , each of which has at least one disk cutter  5  adjoining excavation face  2  during excavation. Disk cutter arrangements  4  are equipped with at least one monitoring device  6  assigned to one disk cutter  5  as devices according to the invention, which are configured to monitor the state of rotation of particular disk cutter  5  of shield tunnel boring machine  1 . 
     Monitoring devices  6  are preferably wirelessly connected to a receiver  7 , which is configured to receive signals emitted by monitoring devices  6 , for example in a so-called star network or mesh network configuration, via a receiving antenna  8  and to transmit them via a data line  9  of a data processing unit  11  situated in a control station  10  of shield tunnel boring machine  1 . Data processing unit  11 , in turn, is connected to a screen  12  of control station  10 , on which the data assigned to the states of rotation of disk cutters  5  are displayed. 
       FIG. 2  shows a perspective view of an exemplary embodiment of a disk cutter arrangement  4  according to the invention, as is present in a shield tunnel boring machine  1  according to  FIG. 1 . Disk cutter arrangement  4  has a disk cutter housing  13  which has an oval shape closed in the manner of a ring. Disk cutter  5  is situated in a disk cutter retaining space  14  enclosed by disk cutter housing  13  on the edge, and it is connected to the disk cutter housing by engaging clamping units  15  on both ends of an axis, around which disc cutter  5  is rotatably supported. Each clamping unit  15  has a clamping screw  16 , by means of which a clamping wedge  17  facing excavation face  2  (not illustrated in  FIG. 2 ) during operation and a clamping block  18  on the side of disk cutter housing  13  facing away from excavation face  2  may be tensioned with respect to each other by tightening a tensioning nut  19  and thereby clamping the fixing of the ends of a disk cutter axis (not visible in  FIG. 2 ) of disc cutter  5 . 
     For tensioning purposes, clamping block  18  is provided with two edge tabs  21 ,  22  adjacent to an outside of disk cutter housing  13 , between which a central section  23  crossed by clamping screw  16  is provided. An end section  24  of clamping block  18  extends from central section  23  in the direction of clamping wedge  17 . Monitoring device  6  is situated between clamping wedge  17  and clamping block  18 . 
     A spacer  25 , which is adapted to the active length of clamping unit  15 , is situated between monitoring device  6  and clamping block  18  to fix monitoring device  6  in the same relative arrangement to disk cutter  5  even in the case of different dimensions of disk cutter housing  13 . 
     A retaining groove  26 , in which monitoring device  6 , clamping wedge  17  and end section  24  of clamping block  18  are situated, is provided in an inside of disk cutter housing  13  facing disk cutter retaining space  14 . It is apparent from  FIG. 2  that the same or essentially the same cross sections of end section  24  of clamping block  18  of monitoring device  6  and clamping wedge  17 , or with the exception of only fractions of the overall dimensions, are configured in such a way that retaining groove  26  is essentially completely filled without any appreciable projection into disk cutter retaining space  14 , so that monitoring device  6  is relatively well protected against mechanical damage. 
       FIG. 3  shows the exemplary embodiment of disk cutter arrangement  4  according to  FIG. 2  without disk cutter housing  13 . It is apparent from  FIG. 3  that a sloping surface of clamping wedge  17  rests against the ends of a disk cutter axis  27 , which rotatably fixes disk cutter  5 , so that, when tensioning nut  19  is tightened, clamping wedges  17  press the ends of disk cutter axis  27  against stationary abutment parts  28  surrounding the ends of disk cutter axis  27  in the shape of a C, due to disk cutter housing  13  (not illustrated in  FIG. 3 ), whereby disk cutter  5  is held stable. Moreover, it is apparent in the representation according to  FIG. 3  that monitoring device  6  has a housing block  29 , which faces away from disk cutter  5  and is manufactured as a casting or is machined from a solid material, and a housing cover  30 , which is mounted on housing block  29  and faces disk cutter  5 , housing block  29  and housing cover  30  forming a housing. Housing cover  30  is equipped with a raised sensor area  31 , which faces a hub  32  of disk cutter  5  and is fitted with a sensor module  33  as a module. In this exemplary embodiment, sensor module  33  has a magnetic field sensor, a temperature sensor and an optional acceleration sensor. In this exemplary embodiment, a number of magnetic transmitters  34 , which are provided, for example, by means of small permanent magnets introduced into hub  32  or by existing magnetic inhomogeneities in the material of disk cutter  5 , are furthermore present in hub  32  of disc cutter  5  facing monitoring device  6 . 
       FIG. 4  shows a perspective view of an extract of the arrangement according to  FIG. 3  in the area of monitoring device  6 . It is apparent from  FIG. 4  that raised sensor area  31  has a curved shape on its inside  35  facing disk cutter axis  27  (not illustrated in  FIG. 4 ) to ensure a contactless arrangement of sensor area  31  which is nevertheless situated in close proximity to hub  32  of disk cutter  5  in the axial direction. It is furthermore apparent from the representation according to  FIG. 4  that housing cover  30  has an indented transmitting area  36  on the side of sensor area  31  facing clamping block  18 , which thus has a relatively great distance from disk cutter  5  for a good propagation of electronic waves emitted via transmitting area  36 . 
       FIG. 5  shows a perspective exploded view of the arrangement according to  FIG. 4 . It is apparent from  FIG. 5  that clamping screw  16  has a threaded section  37 , provided with an outer thread, and a smooth-walled shaft section  38 , which is connected to clamping wedge  17 . A ball cup  39  and a spherical disk  40  are situated between tensioning nut  19  and clamping block  18 , by means of which positional tolerances may be compensated by tightening tensioning nut  19 . 
     Spacer  25  is designed to have a central insertion recess  41 , through which the free end of clamping screw  16  passes. Spacer  25  has a through-hole  42 ,  43  on each side of insertion recess  41 , which are flush with inner threaded holes provided in terminal block  18  in a flush arrangement of spacer  25  with end section  24  of terminal block  18 . 
       FIG. 5  furthermore shows that housing block  29  of monitoring device  6  has a cuboid structure and, in this exemplary embodiment, has a centrally located bushing base  44  situated in the central area and extending in a longitudinal direction as well as in a transverse direction of housing block  29 . A shaft channel  45 , through which shaft section  38  of clamping screw  16  passes, extends through bushing base  44 . The diameter of shaft section  38  and shaft channel  45  are configured in such a way that housing block  29  is mounted on clamping screw  16  with a certain clearance in the radial direction. Housing block  29  has through-holes  46 ,  47  on both sides of shaft channel  45 , which lie in the extension of the inner threaded holes as well as through-holes  42 ,  43  of spacer  25  in flush alignment of monitoring device  6  with spacer  25  and with end section  24  of clamping block  18 , so that housing block  29  is detachably fixedly connectable to clamping block  18  using fastening screws, which are not illustrated in  FIG. 5 , as the sole fastening means. 
     A number of retaining spaces  48 ,  49 ,  50  are provided on both sides of bushing base  44  in housing block  29 . In an edge wall  51  of housing block  29  which terminates retaining spaces  48 ,  49 ,  50  on the outside, a number of fastening holes  51  provided with an inner thread are present, into which cover fastening screws  52  may be screwed, which pass through cover fastening holes provided in housing cover  30  for the purpose of connecting housing cover  30  tightly to housing block  29  with the aid of a flat seal situated between housing block  29  and housing cover  30 . 
     It is furthermore apparent from the representation according to  FIG. 5  that, in addition to sensor module  33 , which is situated in raised sensor area  31  and is held there by screwing and casting with a filling compound, monitoring device  6  also has a coupling module  53 , a power supply module  54  and an electronic module  55  as additional modules, coupling module  53  and electronic module  55  being situated in associated retaining spaces  48 ,  50  and held in placed with the aid of a mechanical connecting unit located in retaining spaces  48 ,  50  and/or a filling compound which is at least partially filled therein. Power supply module  54  is exchangeable and is held in its retaining space  49  protected against external influences. 
     In this exemplary embodiment, sensor module  33  has a magnetic field sensor for detecting preferably the rotational speed, however at least the rotation or standstill of disk cutter  5 , as well as a temperature sensor. Power supply module  54  is configured to autonomously supply monitoring device  6  with electrical energy. 
     Coupling module  53  is configured to be inductively connectable to a programming interface for the purpose of integrating monitoring device  6  into the wireless network described in connection with  FIG. 1  via electronic module  55 . 
     Finally,  FIG. 5  shows, as another module, a transmitter module  56  having an antenna, which is situated by casting in transmitting area  36  of housing cover  30  with the aid of screw connections as well as with the aid of a filling compound which is highly resistant to a wide range of stresses. 
     Cables, which are not illustrated in  FIG. 5 , are provided to connect the modules formed by sensor module  33 , coupling module  53 , power supply module  54 , electronic module  55  and antenna module  56 . 
       FIG. 6  shows a block diagram of the electronic structure of monitoring device  6  and its interaction with receiver  7 . For the sake of better understanding,  FIG. 6  shows connections transmitting electrical energy by means of solid lines, connections transmitting control signals by means of dashed lines and connections transmitting data signals with the aid of dotted lines. 
     Sensor module  33 , electronic module  55  and antenna module  56  may be supplied with electrical energy by power supply module  54 . It is apparent from  FIG. 6  that monitoring device  6  is inductively programmable energy-autonomously via coupling module  53  with the aid of a programming interface  57 . Individual modules  33 ,  53 ,  54 ,  55 ,  56  are connected to each other via control signal lines and data signal lines. 
     While this invention has been described as having a preferred design, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.