▎ 摘　　要

NOVELTY - The pneumatic tire (2) comprises a stud (10) that is installed inside a block (6) of a tread (4). A stud variable control device (20) is installed so as to be pushed or pulled according to an appropriate signal. The stud variable control device is installed to be in contact with the stud under the block, in which the stud is embedded. The variable stud control device includes graphene. An electronic control device is installed in the vehicle so that the graphene can be controlled with an electric signal when the driver operates. USE - Pneumatic tire for use in an electric vehicle. ADVANTAGE - Pneumatic tire allows the stud to be easily pushed when the electric energy accumulated in graphene is applied to the variable material due to the rolling motion of the tire. By allowing the stud to be used only on ice and snowy roads, there is an effect of improving the grip of the tire and preventing damage to the road. By allowing the stud to be used without damaging the road, there is an effect of securing driving performance not only on road protection but also on ice and snowy roads. By allowing the studs to be variably controlled and used, it is possible to reduce troublesome replacement of tires, thus eliminating the purchase of seasonal tires and reducing the maintenance cost of the tires. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a pneumatic tire. Pneumatic tire (2) Tread (4) Block (6) Stud (10) Stud variable control device (20)