Patent ID: 6849222

Claim:
A method of manufacturing a ceramic honeycomb structure in which a part of the cell ends located on an end surface of the honeycomb structure are closed, comprising the steps of: fabricating a honeycomb structure body with the cell ends opened at the end surfaces and closing a part of the cell ends at an end surface of the honeycomb structure body, the cell end closing step including the substeps of; attaching a film to said end surface of the honeycomb structure body in such a manner as to cover at least a part of the cell ends, forming through holes by thermally melting or burning off the film located at the cell ends to be closed, dipping said end surface in a slurry containing an end surface closing material thereby to cause the slurry to enter the cell ends by way of the through holes, and hardening the slurry while at the same time removing the film, wherein said through holes are formed in the film by radiating a high-density energy beam to the film and thereby melting or burning off the film, wherein said through holes are formed using the high-density energy beam in such a manner that the high-density energy beam is radiated first at the center of each through hole to be formed and the position of radiation is relatively displaced spirally to Increase the diameter of the through hole to the desired size, and wherein a transparent or translucent film is used and the positions to be irradiated with the high-density energy beam are determined based on the positional information of the cell ends acquired by an image processing means for recognizing the positions of the cell ends visually through the film attached to the end surface of the honeycomb structure body, wherein the image processing means produces the positional information of the cell ends in such a manner that said end surface of the honeycomb structure body is segmented into a plurality of blocks, for each of which the image data for an area including the particular block and a portion duplicated with at least a part of an adjacent block is collected, and the image data for all the blocks are couple to each other by superposing the duplicated areas thereby to produce the positional information on the cell ends for the entire end surface.