Automatic elastomer extrusion apparatus and method

Abstract

The present invention relates to an automatic elastomer extrusion apparatus and method. An apparatus 400 for in-situ extrusion of an elastomeric coating 410 on a profiled helical surface 450 can include a template ( 100, 200 ) forming a gap between the profiled helical surface 450 and an adjacent profiled helical surface ( 102, 202 ) of a template ( 100, 200 ) itself to extrude an elastomer therethrough. A tracking mechanism 302 and/or carriage 300 can allow a template to follow the contours of the profiled helical surface 350 . The apparatus can include means for providing relative movement between the profiled helical surface and the template. The apparatus ( 500, 600 ) can include a cleaning module ( 502, 602 ), an adhesive application module ( 504, 604 ), an elastomer deposition module ( 506, 606 ), and/or a curing module ( 508, 608 ). Each module can further include a template ( 100, 200 ) and/or a tracking mechanism 302.

1 . An apparatus for extruding an elastomeric coating on a profiled helical surface comprising:
 a template having a surface spaced relative to the profiled helical surface to create a gap therebetween;   a source of an elastomer in communication with the gap;   means for extruding the elastomer through the gap; and   at least one tracking mechanism connected to the template and retained against the profiled helical surface.   
   
   
       2 . The apparatus of  claim 1  wherein the profiled helical surface is an interior surface of a stator. 
   
   
       3 . The apparatus of  claim 1  wherein the profiled helical surface is an exterior surface of a rotor. 
   
   
       4 . The apparatus of  claim 1  further comprising means for providing relative axial movement between the profiled helical surface and the template. 
   
   
       5 . The apparatus of  claim 1  wherein the at least one tracking mechanism is at least one wheel. 
   
   
       6 . The apparatus of  claim 5  further comprising a drive apparatus connected to the at least one wheel. 
   
   
       7 . The apparatus of  claim 1  further comprising:
 means for removing a pre-existing elastomeric coating from the profiled helical surface;   means for applying an adhesive on the profiled helical surface; and   means for curing the elastomeric coating.   
   
   
       8 . The apparatus of  claim 7  further comprising means for providing relative movement between the profiled helical surface and the apparatus. 
   
   
       9 . The apparatus of  claim 7  further comprising means for providing relative movement between the profiled helical surface and each of the template and the respective means for removing, applying, and curing. 
   
   
       10 . An apparatus for extruding an elastomeric coating on a profiled helical surface comprising:
 a carriage disposed adjacent the profiled helical surface;   a cleaning module, an adhesive application module, an elastomer deposition module comprising a template having a surface spaced relative to the profiled helical surface to create a gap therebetween and a source of an elastomer in communication with the gap, and a curing module each disposed on the carriage; and   a traversal apparatus connected to the carriage for traversing the profiled helical surface.   
   
   
       11 . The apparatus of  claim 10  wherein the elastomer deposition module further comprises means for extruding the elastomer through the gap. 
   
   
       12 . The apparatus of  claim 10  wherein the elastomer deposition module further comprises at least one displacement servo to maintain an orientation of the template relative to the profiled helical surface. 
   
   
       13 . The apparatus of  claim 10  wherein the carriage further comprises at least one displacement servo to maintain an orientation of an assembly of the modules relative to the profiled helical surface. 
   
   
       14 . The apparatus of  claim 10  wherein the adhesive application module further comprises:
 a second template having a surface spaced relative to the profiled helical surface to create a second gap; and   a source of an adhesive in communication with the second gap.   
   
   
       15 . The apparatus of  claim 14  wherein the adhesive application module further comprises at least one displacement servo to maintain an orientation of the second template relative to the profiled helical surface. 
   
   
       16 . The apparatus of  claim 10  wherein the cleaning module is disposed adjacent a first end of the carriage and the curing module adjacent a second end of the carriage, the adhesive application module being disposed adjacent the cleaning module and the elastomer deposition module being disposed between the adhesive application module and the curing module. 
   
   
       17 . The apparatus of  claim 10  wherein the traversal apparatus comprises at least one tracking mechanism retained against the profiled helical surface. 
   
   
       18 . The apparatus of  claim 17  wherein the carriage is rotatable about a longitudinal axis of the profiled helical surface. 
   
   
       19 . The apparatus of  claim 17  further comprising a rotational drive apparatus connected to the profiled helical surface to rotate the profiled helical surface during deposition of an elastomer. 
   
   
       20 . The apparatus of  claim 19  wherein the traversal apparatus further comprises a guide connected to the carriage and following at least one track extending in a straight line parallel to a longitudinal axis of the profiled helical surface as the profiled helical surface is rotated relative to the at least one track. 
   
   
       21 . The apparatus of  claim 10  wherein the carriage comprises a plurality of interconnected circular body members retained coaxial to a longitudinal axis of the profiled helical surface by a plurality of tracking mechanisms retained against the profiled helical surface and circumferentially mounted on the plurality of circular body members. 
   
   
       22 . The apparatus of  claim 10  wherein the traversal apparatus comprises at least one wheel resiliently held against the profiled helical surface. 
   
   
       23 . The apparatus of  claim 22  further comprising a drive apparatus connected to the at least one wheel to drive the carriage along the profiled helical surface. 
   
   
       24 . A method of extruding an elastomeric coating on a profiled helical surface comprising:
 providing a template having a surface spaced relative to the profiled helical surface to create a gap therebetween, the gap in communication with a source of an elastomer;   extruding the elastomer on the profiled helical surface through the gap; and   providing relative movement between the profiled helical surface and the template, the template tracking the profiled helical surface with at least one wheel retained against the profiled helical surface.   
   
   
       25 . The method of  claim 24  wherein the step of providing relative movement comprises powering a drive apparatus connected to the at least one wheel. 
   
   
       26 . A method of extruding an elastomeric coating on a profiled helical surface comprising:
 disposing a carriage with a cleaning module, an adhesive application module, an elastomer deposition module, and a curing module mounted thereto along the profiled helical surface;   removing a pre-existing elastomeric coating with the cleaning module from a section of the profiled helical surface as the carriage is disposed along the profiled helical surface;   applying an adhesive with the adhesive application module on the section of the profiled helical surface where the pre-existing elastomeric coating has been previously removed by the cleaning module;   extruding an elastomer through a gap formed between a template of the elastomer deposition module and the profiled helical surface on the section of the profiled helical surface where the pre-existing elastomeric coating has been previously removed with the cleaning module and the adhesive has been previously applied with the adhesive application module; and   curing the elastomeric coating with the curing module on the section of the profiled helical surface where the cleaning, adhesive application, and elastomer deposition modules have previously removed the pre-existing elastomeric coating, applied the adhesive, and deposited the elastomeric coating.   
   
   
       27 . The method of  claim 26  further comprising positioning the template with at least one tracking mechanism connected to the template and retained against the profiled helical surface. 
   
   
       28 . The method of  claim 26  further comprising positioning the template with at least one displacement servo disposed between the template and the carriage. 
   
   
       29 . The method of  claim 26  wherein each of the cleaning, applying, extruding, and curing steps occur concurrently. 
   
   
       30 . The method of  claim 26  further comprising providing relative movement between the carriage and the profiled helical surface during the cleaning, applying, extruding, and curing steps. 
   
   
       31 . The method of  claim 26  further comprising providing relative movement between the carriage and each of the cleaning module, the adhesive application module, the elastomer deposition module, and the curing module during the cleaning, applying, extruding, and curing steps. 
   
   
       32 . The method of  claim 26  further comprising:
 connecting a guide to the carriage, the guide following at least one track extending in a straight line parallel to an axis of the profiled helical surface;   connecting at least one tracking mechanism to the carriage, the at least one tracking mechanism retained against the profiled helical surface; and   imparting relative rotation between the profiled helical surface and the carriage to drive the carriage along the track and the profiled helical surface.