3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

Steven J Lenius

John W Louks

Ronald P Swanson

Eugen Will

Malcolm F Douglas

David W Osten

Mark A Berman

Graham V Jackson

Anatoly Akselrod

James B Cysewski

Joseph W Petrin

A coater for separating primary particles that are coated with a sticky or tacky resin, and covering the surface of the primary particles with a secondary particle of smaller size is disclosed. The coater includes a disc having a periphery, a motor engaging the disc so as to be able to spin the disc, and a restrictor mounted adjacent to the disc so as to provide a gap for the egress of coated particles near the periphery of the disc. Other embodiments of the invention will also have a first dispenser for particles disposed above the disc. Also conveniently, the coater will also have a second dispenser for particles disposed above the disc. In one application for which the coater can be employed, the first dispenser will be adapted to dispense a mixture of sand particles and polymeric resin, and the second dispenser will be adapted to dispense retroreflective glass beads.

Disc coater

Method of producing sheet material incorporating particulate matter

An open tube apparatus and method for continuously producing a rotating elongate strip of material are disclosed. An extrusion die continuously extrudes flowable material to form an open tube with a central longitudinal cavity and a transport mechanism includes a plurality of drive rollers which engage and pull the tube downline. A driver rotates the extrusion die and transport mechanism. A tube cutter, which is offset at an angle with respect to the downline direction and defines the open end of the tube, cuts the tube into a continuous elongate web of the desired width as the tube moves downline. An air seal seals the tube cavity to prevent air from escaping through the open end of the cavity, and a tube pressurizer controls air pressure in the central longitudinal cavity of the tube to expand the tube laterally outwardly.

Apparatus and method for producing an elongate strip of material

A constraining structure for an open tube apparatus for continuously producing a rotating elongate strip of material is disclosed. The constraining structure controls expansion of an extruded blown film tube to a desired outer diameter range after the tube is formed. The constraining structure includes a casing positionable around the tube, and an annular sleeve in the casing having a generally cylindrical central passageway adapted to receive the tube to permit movement of the tube along its longitudinal axis in a downline direction. The casing and the sleeve walls define a gas chamber with pressurized gas separate from the passageway. The gas layer along the inner surface of the sleeve is at a sufficiently large pressure to constrain the tube to the desired outer diameter while the tube solidifies and to prevent the tube from contacting the sleeve.

Apparatus and method for constraining a rotating tube of material

Growing community of inventors

Woodbury, MN, United States of America

Steven J Lenius