Apparatus for co-extruding a rubber strip of one material with a stripe of a second material
AssigneeGenCorp Inc.
InventorDon J. Linnstaedter
Life of this patent
Estimating the term…
Abstract
The extrusion of a tire sidewall or tread and sidewall strip with a white sidewall stripe integrally formed therewith is made possible by an improved, modified preform unit for extrasion die. The preform unit has a first passageway for the sidewall or tread-sidewall strip that extends from the entrance side through to the exit side of the unit. The unit is modified to include a second passageway for the white sidewall material that introduces the white material into the stream of the black sidewall material as it passes through the unit. Upstream of the point where the white side material is introduced, the blockage means interrupts the flow of the black material, creating a void in the stream into which the white material can flow.
Claims3
Apparatus for extruding a strip having a main body of a first material and a lengthwise extending stripe of a second material, said apparatus including a unit with an entry side and an exit side and a first passageway for said first material having a cross-section of relatively wide width and a relatively narrow height, said first passageway extending through said unit from said entry side to said exit side, and a second passageway for said second material intersecting said first passageway at an orifice located on a portion of a widthwise extending edge of said passageway cross-section and between said entry side and exit side of said unit, means on said entry side of said unit for forcing said first material through said first passageway, and means for forcing said second material through said second passageway and into said first passageway through said orifice, characterized by the improvement comprising,
- blocking means interrupting said first passageway at a location upstream from the location where said second passageway interrupts said first passageway, said blocking means extending across the height of said cross-section of said first passageway and over substantially the same widthwise portion of said cross-section as said orifice, but being spaced from the ends of said widthwise extending edge of the cross-section,
- a tube extending from said end surface of said unit through said unit parallel to and spaced from said widthwise edge surface of the elongated cross-section of said first passageway, said tube forming the wall of said entry portion of said passageway and having an elongated hole at the location where said exit portion intersects said entry portion of said second passageway, said elongated hole extending parallel to and facing said widthwise edge of the cross-section of said first passageway.
Dependencies are inferred from the claim text.