Snow horns

Abstract

A device for dispensing carbon dioxide snow in the form of a ribbon includes a conduit into which liquid CO.sub.2 is expanded to form solid and gaseous carbon dioxide which in turn is directed as a stream into a curved horn section of increasing, rectangular cross sectional area. The gaseous and solid CO.sub.2 stream is deflected to the outer curved portion of the horn section and ambient atmosphere is introduced therein to create a pressure differential that causes solid CO.sub.2 to be spread evenly along the outer curved section. Solid carbon dioxide is discharged from the outlet of the horn section onto a moving surface in the form of a ribbon having a width approximately equal to the width of the horn section and at a uniform depth. Ribbons of such solid carbon dioxide may be formed on conveyor belts of freezing tunnels to enable refrigeration to be applied to the underside of items placed on such ribbons of CO.sub.2 snow.

Dependencies are inferred from the claim text.