Abstract:
An apparatus for orienting section of a plasticized ceramic extrudate includes a marking assembly for applying an orientation reference mark to a plasticized ceramic extrudate exiting an extrusion die onto an extrudate support, and at least one extrudate-contacting deformable roller having an axis of rotation, wherein the axis of rotation is pivotable with respect to a movement of the extrudate exiting an extrusion die, and wherein the roller is adapted to contact the extrudate and correct a corkscrew deformation of the extrudate exiting the extrusion die. The apparatus also includes at least one extrudate-contacting orientation control member for correcting the orientation of a cut section of the extrudate on the extrudate support in response to a misalignment of the reference mark. The apparatus further includes at least one gripping member adapted to laterally transfer the cut section of the extrudate along a linear path with respect to the extrudate support while preventing any orientation change of the cut section of the extrudate support, and a visual inspection apparatus adapted to confirm the orientation of the cut section of the extrudate on extrudate support.

Description:
BACKGROUND OF THE INVENTION 
   The invention relates to an extruded ceramic log transfer system, and more specifically to an automated extruded ceramic log transfer system. 
   Extruded logs or extrudates of ceramic are used in a wide variety of applications, such as substrates for automotive exhaust catalytic converters, particulate traps within diesel engines, chemical filtration processes, and the like. The manufacturing process for these extrudates typically include the transfer of the wet log along a manufacturing line or cell subsequent to being extruded from an associated extrusion die. 
   Heretofore, this transfer is typically conducted via a manual process that requires an operator to physically touch the ceramic extrudate either hand-and/or a utensil. The forces as exerted by the operator onto the ceramic extrudate when touching the same are variable in nature and differ from operator to operator and part to part, thereby resulting in a non-uniform deformation of the extrudate during processing. As in many industries, the dimensional requirements for these extrudates continue to be narrowed, thereby making the manual deformation of these filters unacceptable. Specifically, the tolerances associated with the alignment of the internal cells of many ceramic extrudates must be closely held to assure proper shape and fluid flow therethrough. Further, the demand for cylindrically-shaped filter bodies has increased dramatically in recent years. The cylindrical shape of these filters makes it inherently difficult to manually handle the same. Moreover, cycle times associated with the manufacturing process are significantly effected by the non-uniform manual feeding process. Another problem associated with manual manipulation of the extrudates includes the variability of locating the ceramic extrudates in a position to be fired or cured without allowing deformation of the associate cells due to gravitational forces. 
   A manufacturing process is therefore desired that removes the inconsistencies associated with manual feeding of an extruded ceramic log or extrudate, including reducing the deformation of the extrudate during the forming process, increasing the precision of alignment of the extrudate prior to curing and/or firing, and decreasing cycle time. 
   SUMMARY OF THE INVENTION 
   One aspect of the present invention is to provide an apparatus for orienting sections of a plasticized ceramic extrudate that includes a marking assembly for applying an orientation reference mark to a plasticized ceramic extrudate exiting an extrusion die onto an extrudate support, and at least one extrudate-contacting orientation control member for correcting the orientation of the cut section of the extrudate on the extrudate support in response to misalignment of the reference mark. The apparatus also includes at least one gripping member adapted to laterally transfer the cut section of the extrudate along a linear path with respect to the extrudate support while preventing any orientation change of the cut section of the extrudate support. The apparatus further includes a visual inspection apparatus adapted to confirm the orientation of the cut section of the extrudate on the extrudate support. 
   Another aspect of the present invention is to provide a method for orienting sections of a plasticized ceramic extrudate that includes applying a reference mark to a plasticized extrudate as the extrudate exits the extrusion die into an extrudate support, and supporting the extrudate on the extrudate support. The method also includes cutting the extrudate to form a cut section of the extrudate, and correcting the orientation of the cut section of the extrudate in response to a reference mark misalignment and as the extrudate is supported by the extrudate support. The method further includes transferring the cut section of the extrudate along a length of the extrudate support while preventing any orientation change of the cut section, and visually inspecting the orientation of the cut section of the extrudate. 
   Yet another aspect of the present invention is to provide an apparatus for orienting sections of a plasticized ceramic extrudate that includes a marking assembly for applying an orientation reference mark to a plasticized ceramic extrudate exiting an extrusion die onto the extrudate support, and at least one extrudate-contacting orientation control member for correcting the orientation of the cut section of the extrudate on the extrudate support in response to a misalignment of the reference mark. 
   Still another aspect of the present invention is to provide an apparatus for correcting deformation of a plasticized ceramic extrudate exiting an extrusion die that includes a support frame, and at least one extrudate-contacting deformable roller operably coupled to support frame and having an axis of rotation, wherein the axis of rotation is pivotable with respect to a movement and extrudate exiting an extrusion die, and wherein the roller is adapted to contact the extrudate and correct a corkscrew deformation of the extrudate exiting the extrusion die. 
   The present inventive methods and associated apparatus disclosed herein are highly consistent and repeatable, remove the inconsistencies associated with prior art methods and apparatus, reduce the deformation of the associated ceramic extrudates as manufactured via prior art systems and methods, increase the precision of alignment prior to curing and/or firing the associated extrudates, reduce manufacturing cycle times, and are particularly well adapted for the proposed use. 
   These and other advantages of the invention will be further understood and appreciated by those skilled in the art by reference to the following written specification, claims and appended drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of an extruded ceramic log transfer system embodying the present invention; 
       FIG. 2  is a top plan schematic view of the transfer system; 
       FIG. 3A  is a partially schematic perspective view of a continuous ink jet system of the transfer system; 
       FIG. 3B  is an extrudate including ink markings applied by the ink jet system; 
       FIG. 4  is a perspective top view of a corkscrew correction roller system of the transfer system; 
       FIG. 5  is a partially schematic perspective view of an automatic log alignment system of the transfer system; 
       FIG. 6  is a partially schematic perspective view of an automatic grab and drag system of the transfer system; and 
       FIG. 7  is a partially schematic top perspective view of a log alignment camera system of the transfer system. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in  FIGS. 1 and 2 . However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
   The reference numeral  10  ( FIGS. 1 and 2 ) generally designates an extruded ceramic log transfer system embodying the present invention. In the illustrated example, the transfer system  10  includes an extrusion apparatus  12  having an extrusion die  13  adapted to form a ceramic extrudate  14 , and a continuous ink jet system or marking assembly  15  for continuously marking the extrudate  14  as it is extruded from the extrusion die  13  onto an extrudate support  25 . The transfer system  10  also includes a corkscrew correction roller system or corkscrew correction assembly  16  that corrects a corkscrew deformation of the extrudate  14  as it is extruded through the extrusion die  13 . The transfer system  10  further includes a wet saw assembly  17  that cuts a portion or segment  18  from the extrudate  14 . An automatic log alignment system or orientation control system  19  is used to properly align the extrudate segment  18  in reference to a reference mark as provided by the inkjet system  15 , as described below. A grab and drag system  20  is utilized to move the extrudate segment  18  in a linear path within the transfer system  10  and repositions the segment  18  from the extrudate support  25  onto a dryer tray  21  for movement along a conveyor system  22 . A wet log alignment camera system or visual inspection system  23  is then utilized to monitor the alignment of the segment  18  as it rests on the associated dryer tray  21 . 
   The inkjet system  15  ( FIG. 3 ) includes an inkjet print head  26  for printing an orientation reference mark  28  ( FIG. 3B ) on the extrudate  14  as the extrudate  14  is extruded from the extrusion die  13 . The print head  26  may further be used to provide a date stamp  30  (or other information for traceability) on the extrudate  14  for the purpose of quality tracking and control. The print head  26  is in fluid communication with an ink reservoir  32 . An optical reader or photo eye  34  is utilized to detect the presence of the extrudate  14 . The print head  26  and the optical reader  34  are in operable communication with a controller  36  that receives the signals from the optical reader  34  and controls the print head  26  in response thereto. It should be noted that print head  26  is located as close as physically possible to the extrusion die  13  so as to accurately mark the extrudate  14  as it is extruded from the extrusion die  13  prior to deformation of the extrudate  14 , such as the corkscrewing effect caused by the extrusion process. Preferably, the ink jet system  15  includes a Linx 4800 continuous inkjet unit as available from Diagraph of St. Charles, Mo., however, other inking systems may be utilized. 
   The corkscrew correction roller system  16  ( FIG. 4 ) includes a frame  38  extending upwardly from the extrudate support  25 , and a vertically adjustable support assembly  40 . The vertical location of the support assembly  40  with respect to the extrudate support  25  is adjusted via a dial  42  operably connected to a threaded adjustment rod  44 , that is in turn threadably coupled with the support assembly  40 . A pair of elastically deformable rollers  46  are supported below the support assembly  40  via a pair of C-shaped hanging brackets  48 . Each roller  46  is cylindrically shaped defining a pivot axis  50 , and are preferably constructed of a material that will not cause deformation of an outer surface of the extrudate  14  while in contact therewith. The hanging brackets  48  are operably coupled to the support assembly  40  such that the rotation of an adjustment handle  52  causes the pivot axis  50  of the rollers  46  to move out of perpendicular alignment with a centroidal axis  54  of the extrudate  14 . 
   In operation, the extrusion die  13  is known to cause a corkscrew deformation of the extrudate  14  as the extrudate  14  is extruded therefrom. As the extrudate  14  moves along the extrudate support  25  in a direction as represented and indicated by arrow  56 , the corkscrew deformation of the extrudate  14  as caused by the extrusion die  13  is corrected by contacting the rollers  46  with an outer surface of the extrudate  14 . Specifically, the pivot axis  50  of each roller  46  is adjusted via the adjustment handle  52  such that the rollers impinge on the outer surface of the extrudate  14  in a direction that causes a counter rotation to the corkscrew deformation. In other words, looking down vertically from above the extrudate  14 , if there is no corkscrew to be corrected for, the pivot axis  50  is perpendicular to the axis  54  of extrudate  14 . If, on the other hand, there is corkscrew present in the extrudate  14 , the pivot axis  50  is askew from perpendicular to the axis  54  of extrudate  14 , to thereby cause counter rotation to the corkscrew deformation. It should be noted that the correction of the corkscrew deformation is conducted prior to the extrudate  14  being cut into the segments  18 , thereby eliminating the requirement to support a free extrudate segment  18  while attempting to correct for the corkscrew deformation. 
   A laser encoder  58  is utilized to monitor the extrusion velocity, i.e., the velocity that the extrudate  14  is extruded from the extrusion apparatus  12 . The velocities as read by the laser encoder  58  are relayed to a controller  59 , that may be included within a central control system, where the velocity readings are utilized to time and sequence the grab and drag system  20  as well as other subsequently completed steps and procedures. A wet saw  17  is then utilized to cut the extrudate segments  18  from the continuous extrudate  14 . As wet saws are generally well known in the art, a detailed description of the same is not provided. 
   The automatic log alignment system  19  ( FIG. 5 ) includes an air bearing  60  having a bearing surface  62  upon which the extrudate segment  18  is free to float once cut from the continuous extrudate  14 . The bearing surface  62  includes a plurality of air jet apertures through which a continuous supply of forced air is exerted therethrough to floatingly support the segment  18  thereon once the segment  18  is cut from the continuous extrudate  14 . The alignment system  19  also includes a camera system that takes an optical reading of the reference mark  28  and communicates the same with a controller  68 , which may be included within a central control system. The controller  68  is in operable communication with an alignment assembly that includes a servo motor  72  operably coupled with a gear box  74 , that is in turn coupled with a support assembly  76  that pivotally supports an elastically deformable roller  78  such that the pivotal axis  80  of the roller  78  can be pivoted about a vertical axis  82 . The roller  78  is preferably constructed of a material that does not cause deformation of the segment  18  when in contract therewith, such as a foam. 
   In operation, the camera system  36  monitors the position of the reference mark  28  and communicates those readings with the controller  68  where the position of the reference mark  28  is compared with a predetermined reference point. Should misalignment occur, the controller  68  operates the servo motor  72  to pivot the support assembly  76  about the axis  82 , thereby moving the pivot axis  80  out of perpendicular alignment with the centroidal axis  54  and causing the segment  18  to pivot about the centroidal axis  54 . 
   The grab and drag system  20  ( FIG. 6 ) includes an overhead frame assembly  90 , a two-axis gantry drive system  96  supported by the frame assembly  90 , and transfer system  98  supported by the drive system  96 . The frame assembly  90  includes a pair of vertical members  92  that support a horizontally-extending track member  94 . The drive system  96  includes a plurality of servo motors and gear assemblies to move the transfer assembly in a horizontal path  100  with respect to the extrudate support  25 , and to adjust the vertical location of the transfer system  98  with respect to the extrudate support  25  along a vertical path  102 . A downwardly-extending support arm  106  supports the transfer system  98  above the extrudate support  25 . The transfer system  98  includes a frame  108  fixedly connected to the support arm  106  and having a proximate end  110 , a distal end  112 , and a pair of pad support portions  114  extending outwardly from a side of the frame  108  between the proximate end  110  and the distal end  112 . Each pad support  114  supports an extrudate segment contacting pad  116  therebelow. Each pad  116  is preferably constructed of a flexibly resilient foam and is arcuately contoured. The arcuate shape is preferably substantially similar to the arcuate shape of the outer surface of the extrudate segment  18 . A pneumatic cylinder  118  is fixedly connected to the frame  108  beneath the proximate end  110  thereof. A rear paddle  120  is connected to the operable end of the pneumatic cylinder  118  and is adapted to contact an end of the extrudate segment  18  as described below. The transfer system  98  further includes a compressed air system  122  having a plurality of switches  124  in operable communication with an air source such as a compressor  126  via a plurality of fluid lines  127 . The air system  122  further includes a plurality of air lines  128  in fluid communication with heads  130  extending through each pad support  114  of the frame  108 . The purpose of the compressed air system is to enable the pads  116  to periodically be “blown out” to remove any debris that may accumulate on the pads during periods of transfer. Preferably, such blowing out of the pads  116  occurs when the pads are not in contact with an extrudate segment  18 , e.g., when the pads are returning to the pick position to engage another extrudate segment  18 . 
   In operation, the controller  132  adjusts the location and height of the transfer system  98  with respect to the extrudate support  25  and begins its horizontal movement. Once a gap is generated between extrudate segment  18  and extrudate  14 , the rear paddle  120  is positioned behind a trailing end  132  of the extrudate segment  18 . The pneumatic cylinder  118  is then utilized to help ensure containment of the extrudate segment  18  with the transfer system  98  by moving the rear paddle  120  inward to contact with the trailing end  132  of the extrudate segment  18 . The extrudate is transferred laterally via. a frictional force between the pads  116  and the segment  18 . The extrudate segment  18  is then moved in a linear path along the continuous air bearing  60  from the extrudate support  25 , position A, to a dryer tray  134 , position B, also including an air bearing  135 . The air bearing is shut off and the extrudate segment  18  rests on the dryer tray  134 . During the return of the transfer system  98  to its original position, a short burst of air from the compressed air system  122  is provided through the pad supports  114  and foam pads  116  to help eliminate any debris. 
   The wet log alignment camera system  23  ( FIG. 7 ) includes a camera  140  and an LED ring light  142  mounted within an housing  144 , and a photo-eye  146 . The camera  140  takes an image of an end  148  of the extrudate segment  18  resting on the dryer tray  134  as the extrudate segment  18  passes by the photo-eye  146  and while the end  148  of the extrudate segment  18  is illuminated by the LED ring light  142 . The image as produced, which includes a section of the end  148  that includes at least twenty-five walls  152 , is communicated with a controller  150  that compared the measured image with a target range for alignment and displays relative information on a display monitor  149  where it is reviewed by the system operator. The controller  150  compares the alignment of the cell structure of the extrudate segment  18  to a predetermined range, as the alignment of the cell structure of each extrudate segment  18  must be closely monitored to ensure proper alignment so as to prevent deformation of the associated cell structure during curing and/or firing. Specifically, the walls  152  cell structure of each segment  18  must be positioned at an angle relative to an absolute vertical/horizontal to eliminate or reduce the amount of deformation, i.e., sagging, of the cell structure as the segment  18  is cured. Preferably, the alignment of the cell structure of the segment  18  is kept within a range of ±3.0°, more preferably within a range of ±2.8°, and most preferably within a range of ±1.8°. In a preferred embodiment, the wet log alignment camera system includes a second camera which takes an image of the end of extrudate  18  which is opposite the end the first camera images. In this way, the images from the two ends can be averaged by a computer, so that, in effect, the resultant image that is compared and/or displayed is an representation of the center region of the extrudate. Likewise, the difference between the images from the two ends can be used to report both the direction and the magnitude of the corkscrew of the extrudate  18 , which can then be used to define the corkscrew correction requirements via an associated adjustment of the corkscrew correction roller system  16 . 
   This information is relayed to the system operator via a color coded alignment matrix  154  on the display monitor  149 . The alignment matrix  154  includes a pair of vertical and horizontal alignment bars for reference, and an indicator bar  160  representing the measured reading from the extrudate segment  18  being monitored. The video monitor  149  also displays a plot  162  of the previous nine readings plus the current reading, thereby allowing the system operator to monitor any progressing trends in the system. The plot  162  includes an outer pair of alignment bars  163  representing the ±2.8° alignment range, and an inner pair of alignment bars  165  representing the ±1.8° range. The system  10  is also configured to automatically divert those segments  18  failing to fall within the acceptable range to an auxiliary path  166  separate from the main conveyor line. Alternatively, the system  10  is configured to require operator removal of the failing segment  18 . A closed loop control system is preferably included which allows for automatic adjustment of the automatic log alignment system  19  controller  68  based on the results of the wet log alignment camera system  23  measurements. 
   The present inventive methods and associated apparatus disclosed herein are highly consistent and repeatedly remove the inconsistencies associated with prior art methods and apparatus, reduce the deformation of the associated ceramic extrudates as manufactured via prior art systems and methods, increase the precision of alignment prior to curing and/or firing the associated extrudates, reduce manufacturing cycle times, and are particularly well adapted for the proposed use. 
   In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the following claims, unless these claims by their language expressly state otherwise.