| 摘要 |
PCT No. PCT/JP83/00443 Sec. 371 Date Aug. 13, 1984 Sec. 102(e) Date Aug. 13, 1984 PCT Filed Dec. 19, 1983 PCT Pub. No. WO84/02497 PCT Pub. Date Jul. 5, 1984.A spike tire for a vehicle and which includes a pin receptacle hole formed on the tread surface of the tire; a spike pin retractably protrudable from the pin receptacle hole; a biasing mechanism for continuously urging the spike pin to protrude from the pin receptacle hole; and an actuating member of a shape memory alloy capable of restoring a memorized shape when warmed to a predetermined temperature by the heat generated in the tire as a result of operation of the vehicle on a non-frozen or snow-free road surface, to thereby retract the spike pin into said tire against the action of the biasing mechanism. The spike pin is automatically protruded and retracted depending upon road conditions based on a temperature difference between a frozen or snowed road surface and a non-frozen snow-free road surface. On a non-frozen bare road, the spike pin is automatically retracted into the pin receptacle hole by restoration of a memorized shape of the shape memory alloy thereby preventing damage and abrasive wear of road surfaces and the resulting generation of pollutional dust. |
