Method and apparatus for retreading a tire
AssigneeOliver Rubber Company
InventorsMichael J. King, Robert A. Flynn, Henry Torrez
Life of this patent
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Abstract
A tire recapping and retreading method and apparatus that includes a rigid, segmented tread mold. The mold is retained in place over the tire carcass and uncured tread material by a resilient elastic tension band or prestressed metal tension springs. Further retaining force is provided by a resilient envelope to complete the formation of the retread when the tire and apparatus is placed in a hot air oven. The use of the rigid segmented mold described eliminates the distortion of the tire carcass by the mold.
Claims16
Apparatus for retreading a prepared tire carcass having uncured retreading material located around the exterior of said tire carcass comprising:
- a tread mold including a plurality of rigid mold segments arranged to expand and contract relative to each other and for allowing said segmented tire mold to expand and contract radially around said retreading material;
- resilient retaining means encircling said segmented tire mold for urging said mold segments toward said tire carcass and for retaining said segmented tire mold as a whole while allowing said segments to expand and contract radially relative to each other;
- and
- a pressure envelope for placement over said mold segments and said tire carcass.
A method for retreading a prepared tire carcass including the steps of:
- encircling the prepared tire carcass with a strip of uncured rubber;
- encircling the uncured rubber and the prepared tire carcass with a rigid segmented tread mold including retaining means having at least one tension spring encircling said rigid segmented mold, to allow radial expansion of said rigid segmented mold and contraction of said rigid segmented mold about the prepared tire carcass;
- placing an elastic pressure envelope around said retaining means, said rigid segmented mold and the prepared tire carcass to resiliently hold the rigid segmented mold in encircling relationship with said uncured rubber and forcing said rigid segmented mold into said uncured rubber;
- applying pressure to the elastic pressure envelope to force said rigid segmented mold into said uncured rubber;
- and
- curing said uncured rubber.
Apparatus for retreading a prepared tire carcass having uncured retreading material located around the exterior of said tire carcass comprising:
- a tread mold including a plurality of rigid mold segments arranged to expand and contract relative to each other and for allowing said segmented tire mold to expand and contract radially for mounting said segmented tire mold on said retreading material;
- retaining means including at least one tension spring encircling said segmented tire mold for allowing expansion radially of said segmented tire mold and contraction of said segmented tire mold, whereby said retaining means urges said rigid mold segments toward said tire carcass;
- and
- a pressure envelope for placement over said mold segments and said tire carcass following mounting of said segmented tire mold on said retreading material.
Dependencies are inferred from the claim text.