Safety device with U-shaped memory alloy

The invention provides a safety device with U-shaped memory alloy. The safety device with the U-shaped memory alloy comprises the U-shaped memory alloy, a switcher, a conductive clamping groove and an insulating vertical isolating face. At the first memory position, a second linear segment is in clamping connection with the bottom of the conductive clamping groove; at the second memory position, the second linear segment is in clamping connection with the insulating vertical isolating face across a first sliding face and a second sliding face. According to the safety device with U-shaped memory alloy, the problem that after a circuit is opened, the shaped memory alloy carries out return deformation to reclose the circuit is well solved, and the using process of the safety device is safer and more reliable.