Safety tire with expansion-deforming toric air bag

Abstract

A toric air bag for a safety tire capable of sufficiently and equally contacting with a full inner face of a tire in the expansion-deformation of the toric air bag by a drop of an internal pressure in the tire, wherein at least an expansion-deforming portion of the toric air bag having a hollow torus shape as a whole is constructed with a tension support member, and to the expansion-deforming portion is given a property indicating a characteristic of extension ratio-tensile force that tensile force per unit width is substantially and gradually increased with the increase of elongation through the expansion-deformation.

1 . A toric air bag adapted to be placed inside a safety tire and, when inflated under a certain internal pressure and expansion-deformed by a drop of an internal tire pressure, subrogates a load support from the tire, 
 wherein at least an expansion-deforming portion of the toric air bag having a hollow torus shape is made of a tension support member and the expansion-deforming portion has a characteristic of extension ratio-tensile force that, as an extension is increased by the expansion-deformation, a tensile force per unit width is gradually increased;    wherein the tension support member is constructed with one or more layers of a composite of fibrous member and rubber; and    wherein the fibrous member is constituted with plural fiber layers in which the layers of fiber materials arranged side-by-side are crossed with each other.    
   
   
       2 . A toric air bag adapted to be placed inside a safety tire and, when inflated under a certain internal pressure and expansion-deformed by a drop of an internal tire pressure, subrogates a load support from the tire, 
 wherein at least an expansion-deforming portion of the toric air bag having a hollow torus shape is made of a tension support member and the expansion-deforming portion has a characteristic of extension ratio-tensile force that, as an extension is increased by the expansion-deformation, a tensile force per unit width is gradually increased;    wherein the tension support member is constructed with one or more layers of a composite of polymer sheet and rubber; and    wherein the polymer sheet in the composite has an initial modulus of 0.1-1.3 GPa, a yield stress of 10-33 MPa and an elongation at break of not less than 20%.    
   
   
       3 . A toric air bag according to  claim 2 , wherein a property that the contacting of the toric air bag with the inner face of the tire is carried out in a plastic deformation zone of the composite is given to the composite arranged in the toric air bag.  
   
   
       4 . A toric air bag adapted to be placed inside a safety tire and, when inflated under a certain internal pressure and expansion-deformed by a drop of an internal tire pressure, subrogates a load support from the tire, 
 wherein at least an expansion-deforming portion of the toric air bag having a hollow torus shape is made of a tension support member and the expansion-deforming portion has a characteristic of extension ratio-tensile force that, as an extension is increased by the expansion-deformation, a tensile force per unit width is gradually increased;    wherein the tension support member is constructed with one or more layers of a composite of polymer sheet or fibrous member and rubber; and    wherein a low-rigidity part is annularly arranged on at least one layer among the two or more composite layers at least arranged over a full circumference of the portion facing to the inner circumferential face of the tire tread portion at one or more symmetrical positions with respect to the equatorial plane of the tire.    
   
   
       5 . A toric air bag according to  claim 4 , wherein the low-rigidity part is arranged at plural places.  
   
   
       6 . A toric air bag according to  claim 4 , wherein a rigidity is gradually changed in the low-rigidity part.  
   
   
       7 . A toric air bag according to  claim 4 , wherein the low-rigidity part is arranged so as to separate away from a side edge of the composite.  
   
   
       8 . A toric air bag according to  claim 4 , wherein the low-rigidity part is constructed with a thinned portion of the composite or with a notched portion formed in the composite.  
   
   
       9 . A toric air bag according to  claim 4 , wherein there are at least two composite layers.