Contoured electrodes for an electrostatic gas pump

Abstract

The present invention achieves high gas flow rates through an electrostatic pump having sharp and blunt electrodes with a corona discharge taking place in the gas gap in between the electrodes. According to certain aspects, the invention comprises a specially shaped blunt electrode that is contoured to maintain a constant or approximately constant distance between the sharp (corona) electrode and the neutralizing surface of the blunt electrode. The contour provides maximum electric field enhancement at the corona electrode and minimizes the electric field at the blunt electrode. This maximizes the non-arcing operating voltage and increases the maximum power output of the corona discharge. The contour also isolates neighboring corona electrodes, preventing their electric fields from interfering with one another and making it possible to increase the density of electrodes which further increases the pumping power of the device.

1 . An apparatus comprising:
 a corona electrode; and   a blunt electrode separated from the corona electrode by a gas gap;   wherein the blunt electrode has a neutralizing surface facing the corona electrode that is contoured so that respective distances between a point on the corona electrode and all points of the neutralizing surface directly underlying the point are substantially constant.   
   
   
       2 . An apparatus according to  claim 1 , wherein the neutralizing surface is further contoured to maximize an electric field enhancement at the corona electrode and increase a maximum power output of a corona discharge occurring in the gas gap. 
   
   
       3 . An apparatus according to  claim 1 , wherein the neutralizing surface faces the corona electrode for a given length thereof, the contour defining a partial hollow cylinder having a height corresponding to the given length and a radius corresponding to the substantially constant distance. 
   
   
       4 . An apparatus according to  claim 1 , wherein the blunt electrode includes a plurality of fins, each fin having a neutralizing surface that faces the corona electrode for a respective given length thereof, the contour of each neutralizing surface defining a partial hollow cylinder having a height corresponding to the respective given length and a radius corresponding to the substantially constant distance. 
   
   
       5 . An apparatus according to  claim 1 , wherein the corona electrode is comprised of a point protruding from a supporting member, and wherein the blunt electrode includes a plurality of fins, each fin having a neutralizing surface that faces the point, the contour of each neutralizing surface defining a partial hollow cylinder having a radius corresponding to the substantially constant distance, and wherein the contours of the plurality of fins collectively define a partial sphere having the radius. 
   
   
       6 . An apparatus according to  claim 1 , wherein the corona electrode is comprised of a plurality of points protruding from a supporting member, and wherein the blunt electrode includes a plurality of fins, each fin having a neutralizing surface that faces a respective one of the points, the contour of each neutralizing surface defining a partial hollow cylinder having a radius corresponding to the substantially constant distance. 
   
   
       7 . An electrostatic gas pump apparatus comprising:
 a plurality of corona electrodes; and   a plurality of blunt electrode fins,   wherein each blunt electrode fin has a neutralizing surface facing certain of the corona electrodes, the neutralizing surface being contoured so that respective distances between a point on the corona electrode and all points of the neutralizing surface directly underlying the point are substantially constant.   
   
   
       8 . An apparatus according to  claim 7 , wherein the neutralizing surface faces the corona electrode for a given length thereof, the contour defining a partial hollow cylinder having a height corresponding to the given length and a radius corresponding to the substantially constant distance. 
   
   
       9 . An apparatus according to  claim 7 , wherein each neutralizing surface of each of the fins faces a respective one of the corona electrodes for a respective given length thereof, the contour of each neutralizing surface defining a partial hollow cylinder having a height corresponding to the respective given length and a radius corresponding to the substantially constant distance, the height corresponding to a thickness of the fin. 
   
   
       10 . An apparatus according to  claim 9 , wherein the corona electrodes are arranged substantially parallel to each other and separated by a corona electrode spacing. 
   
   
       11 . An apparatus according to  claim 9 , wherein the corona electrodes are arranged substantially parallel to each other and separated by a corona electrode spacing, and the fins are arranged substantially parallel to each other, and substantially perpendicular to the corona electrodes, and separated by a fin spacing. 
   
   
       12 . An apparatus according to  claim 11 , wherein the fin spacing between the fins define corresponding channels for the flow of gas caused by an electrostatic discharge between the electrodes. 
   
   
       13 . An apparatus according to  claim 11 , further comprising walls that are arranged parallel to the corona electrodes and connect the blunt electrode fins, each wall separating a corresponding adjacent pair of neutralizing surfaces in each of the fins. 
   
   
       14 . An apparatus according to  claim 13 , wherein the fin spacing between the fins and the walls between the adjacent pairs of neutralizing surfaces define corresponding channels for the flow of gas caused by an electrostatic discharge between the electrodes. 
   
   
       15 . An apparatus according to  claim 7 , wherein the neutralizing surface is contoured so as to isolate neighboring corona electrodes, preventing their electric fields from interfering with one another and thereby increasing the pumping power of the electrostatic pump apparatus. 
   
   
       16 . An electrostatic pump apparatus, comprising:
 an array of corona discharge regions, wherein each discharge region includes a contoured neutralizing surface of a blunt electrode.   
   
   
       17 . An apparatus according to  claim 16 , wherein the array comprises a plurality of corona electrodes arranged substantially in parallel to each other and a plurality of blunt electrode fins arranged substantially in parallel to each other and substantially perpendicular to the corona electrodes, the corona discharge regions being respectively located at intersections between the corona electrodes and blunt electrode fins. 
   
   
       18 . An apparatus according to  claim 17 , wherein the neutralizing surface in each corona discharge region faces the corona electrode and is contoured so that respective distances between a point on the corona electrode and all points of the neutralizing surface directly underlying the point are substantially constant. 
   
   
       19 . An apparatus according to  claim 17 , wherein the neutralizing surface in each corona discharge region is contoured so as to isolate it from neighboring corona discharge regions, preventing their electric fields from interfering with one another and thereby increasing the pumping power of the electrostatic pump apparatus. 
   
   
       20 . An apparatus according to  claim 17 , further comprising walls that are arranged parallel to the corona electrodes and connect the blunt electrode fins, each wall separating a corresponding adjacent pair of neutralizing surfaces in each of the fins.