Retreaded tires and method for making the same without spray cement

Abstract

A retreaded tire assembly and method for making the same is disclosed. The method and assembly provide for the application of new tread to a buffed tire casing with only a layer of cushion gum disposed therebetween. The cushion gum is applied directly to the buffed circumference of a tire casing without the use of conventional spray cement normally applied to the buffed surface of the entire casing.

What is claimed is:  
     
         1 . A method for retreading a tire, comprising the steps of: 
 removing tire tread from a tire casing to present a buffed surface;    applying a layer of cushion gum directly to the buffed surface;    wrapping a tread layer about the layer of cushion gum; and    treating the tire to form bonds between the casing and the layer of cushion gum and between the tread layer and the layer of cushion gum.    
     
     
         2 . The method for retreading a tire as recited in  claim 1 , wherein the step of applying the layer of cushion gum includes the step of pressing the layer of cushion gum against the buffed surface with sufficient pressure to force any air from between the casing and the layer of cushion gum.  
     
     
         3 . The method for retreading a tire as recited in  claim 2 , wherein the step of applying the layer of cushion gum includes stretching the layer of cushion gum circumferentially about the casing.  
     
     
         4 . The method for retreading a tire as recited in  claim 1 , wherein the step of applying the layer of cushion gum includes the step of applying a pair of shoulder strips to the buffed surface.  
     
     
         5 . The method for retreading a tire as recited in  claim 3 , wherein the step of applying the layer of cushion gum includes the steps of cutting the layer generally transverse to the circumferential direction and splicing the layer at the cut region.  
     
     
         6 . The method for retreading a tire as recited in  claim 5 , wherein the step of wrapping the tread layer includes the steps of cutting the tread layer generally transverse to the circumferential direction and splicing the tread layer at the cut region.  
     
     
         7 . The method for retreading a tire as recited in  claim 6 , further comprising the steps of enclosing the tire in an envelope; heating the tire; applying a vacuum within the envelope; and applying pressure to the outside of the envelope.  
     
     
         8 . A method for retreading a tire, comprising the steps of: 
 removing old tire tread from a tire casing to present a buffed surface;    cutting a tread layer to a length sufficient to encircle the buffed surface along the circumference of the casing;    maintaining the buffed surface free of tire retreading cement;    disposing a layer of cushion gum between the buffed surface and the tread layer;    squeezing the layer-of cushion gum between the buffed surface and the tread layer; and    heating the combined tire casing, tread layer and layer of cushion gum to form a vulcanized bond therebetween.    
     
     
         9 . The method for retreading a tire as recited in  claim 8 , wherein the step of removing old tire tread includes grinding the tire tread from the tire casing.  
     
     
         10 . The method for retreading a tire as recited in  claim 9 , wherein the step of maintaining the buffed surface includes removing contaminants from the buffed surface.  
     
     
         11 . The method for retreading a tire as recited in  claim 8 , wherein the step of disposing the layer of cushion gum includes applying tension thereto in a circumferential direction as the layer of cushion gum is wrapped about the circumference of the tire casing.  
     
     
         12 . The method for retreading a tire as recited in  claim 11 , wherein the step of disposing the layer of cushion gum includes stitching the layer of cushion gum to the buffed surface to drive air from therebetween.  
     
     
         13 . The method for retreading a tire as recited in  claim 8 , wherein the step of squeezing includes the steps of placing the combined tire casing, tread layer and layer of cushion gum within a pressure chamber.  
     
     
         14 . The method for retreading a tire as recited in  claim 13 , wherein the step of squeezing includes the steps of placing the combined tire casing, tread layer and layer of cushion gum within an envelope and creating a vacuum within the envelope.  
     
     
         15 . The method for retreading a tire as recited in  claim 14 , wherein the step of heating occurs while the combined tire casing, tread layer and layer of cushion gum are in the pressure chamber.  
     
     
         16 . A retreaded tire assembly prepared for insertion into a pressurized heating chamber comprising: 
 a tire casing having a pair of sidewalls and a radially outer wall spanning the pair of sidewalls, the radially outer wall having a buffed surface disposed about the outer circumference of the tire casing;    a layer of cushion gum disposed directly against the buffed surface; and    a tread layer disposed against the cushion gum.    
     
     
         17 . The retreaded tire assembly as recited in  claim 16 , wherein the layer of cushion gum is mounted in tension about the circumference of the tire casing.  
     
     
         18 . The retreaded tire assembly as recited in  claim 17 , wherein the layer of cushion gum includes a center strip and a pair of shoulder strips.  
     
     
         19 . The retreaded tire assembly as recited in  claim 17 , wherein the tread layer is arcuate in both the circumferential and the transverse directions.  
     
     
         20 . The retreaded tire assembly as recited in  claim 17 , wherein the tread layer is arcuate only in the circumferential direction.