Method and apparatus for decorative etching of surfaces

Apparatus for etching a workpiece such as a sheet of glass or the like with abrasive particles that are propelled against a surface portion of the workpiece, comprising:

• a stand with a generally horizontal workpiece support at the top thereof;
• means defining an opening in said support over which a portion of said workpiece may be placed;
• a hopper located below said opening, spaced from said support and adapted to contain a quantity of said abrasive particles;
• fluid pressure means including a nozzle mounted in said hopper for directing a gaseous stream at relatively high velocity upwardly through said hopper toward said opening whereby abrasive particles in said hopper become entrained in said stream and are carried thereby toward said opening to strike said surface portion of said workpiece;
• filter means interposed between the top of said hopper and said workpiece support and defining an open space between said opening and said hopper whereby gases may pass therethrough outwardly from said space and said abrasive particles entrained in said gases will be filtered out;
• movable shield means adapted to be selectively positioned over said opening and being movable between a retracted position and a protective operating position closely spaced above said opening;
• and
• means responsive to said shield means whereby said gaseous stream is directed through said hopper only when said opening is in its protective operating position.