Abrasive blast cabinet

A blast cabinet for cleaning surfaces of articles with an abrasive blast media comprising

• a housing defining a blast chamber with an interior;
• a blast nozzle disposed in said blast chamber and connected to a source of an abrasive blast media for directing a flow of the blast media carried in a stream of air under pressure against the surface of an article to be cleaned located inside said blast chamber whereby spent blast media normally is dispersed throughout said blast chamber in a manner so as to obscure visual observation of a portion of the article being cleaned from outside said blast chamber;
• window means for observing the article during cleaning including an elongated tubular member having an interior an inner end portion extending into the interior of said blast chamber and an outlet opening into said blast chamber which serves as an inner viewing port situated in the vicinity of but spaced from the article to be cleaned so there is a viewing zone between said inner viewing port and the article to be cleaned, said tubular member further having an outer end portion including a transparent window member closing the interior of said tubular member and cooperating therewith to define an outer viewing port through which an operator located outside said blase chamber can direct his or her line of sight through the interior of said tubular member to observe the article being cleaned through said inner viewing port;
• air inlet means open to the atmosphere and connected in fluid communication with the interior of said tubular member at a location spaced inwardly from said window in a direction toward the interior of said blast chamber;
• and
• ventilation means for removing spent blast media from said blast chamber and for drawing ambient air through said inlet means and through said tubular member for discharge into said viewing zone at a velocity and volume sufficient to provide a purging action for purging away a sufficient amount of spent blast media dispersed in said viewing zone to facilitate observation of at least the portion of the article being cleaned through said outer viewing port.

Apparatus for cleaning the surfaces of articles with a cleaning media comprising

• a housing defining a cleaning chamber;
• cleaning means in said chamber for directing a pressurized flow of the cleaning media against a surface of an article to be cleaned located inside said chamber whereby spent cleaning media normally is dispersed throughout said chamber in a manner so as to obscure visual observation of a portion of the article being cleaned from outside said chamber;
• observation means for observing the article during cleaning from outside said chamber and having a viewing portion extending into said chamber in the vicinity of but spaced from the article to be cleaned such that there is a viewing zone between said viewing portion and the article to be cleaned;
• and
• gas delivery means for directing a flow of gas into said viewing zone to provide a purging action for purging away a sufficient amount of spent cleaning media dispersed in said viewing zone to facilitate observation via said observation means of at least that portion of the article being cleaned.

A blast cabinet for cleaning surfaces of articles with an abrasive blast media comprising

• a housing defining a blast chamber;
• a blast nozzle disposed in said blast chamber and connected to a source of an abrasive blast media for directing a flow of the blast media carried in a stream of gas under pressure against a surface of an article to be cleaned located inside said blast chamber whereby spent blast media normally is dispersed throughout said blast chamber in a manner so as to obscure visual observation of a portion of the article being cleaned from outside said blast chamber;
• an optical lens assembly for observing the article during cleaning and having a viewing portion situated in said chamber in the vicinity of but spaced from the article to be cleaned so there is a viewing zone between said viewing portion and the article to be cleaned, said lens assembly operably connected to a visual monitor remote from said blast chamber to produce a visual image of at least that portion of the article being cleaned on said visual monitor;
• and
• gas delivery means for directing a flow of gas into said viewing zone to provide a purging action for purging away a sufficient amount of spent blast media dispersed in said viewing zone to facilitate observation on said visual monitor of at least the portion of the article being cleaned.

Apparatus for cleaning the surfaces of articles with a cleaning media comprising

• a housing defining a cleaning chamber;
• a directing device disposed in said chamber to direct a pressurized flow of the cleaning media against a surface of an article located inside said chamber;
• an observation device disposed to permit observation of the article during cleaning and having a viewing portion extending into said chamber such that there is a viewing zone between said viewing portion and the article;
• a fluid inlet in said housing;
• and
• a fluid guiding device in fluid communication with said fluid inlet and disposed to guide a flow of gas into said viewing zone.