| 摘要 |
PURPOSE:To prevent damages of road surfaces and to reduce noises by planting spike pins moved back and forth by an oil pressure on the tread face of a snow tire and by moving them back and forth by an operation of a master cylinder so that the tire can be used for running under an optimum method for road conditions. CONSTITUTION:When an oil pressure is applied by an operation of a lever 4A, a piston ring 5c acts outward and spike pins 5d protrude through the tread face, thus forming a spike tire. The protrusion size is made 2-3mm.. When the oil pressure is released by the lever 4A, the spike pins are retreated by return springs 5E, resulting in a snow tire. Accordingly, the tire can be used in a snow tire status on a road with no snow coverage and with exposed asphalt, and also can be used as a spike tire on a road covered with snow, and the operation can be performed very simply and reliably. |
