To obtain improvement of spring characteristics of a contact member with its body part maintained in a small diameter, as to one equipped with an outer periphery side contact part and an inner periphery side contact part and of a structure in which the body part is twisted as it is pressed to have the inner periphery side contact part come in contact with the outer periphery side contact part.

The body part developed consists of nearly a sigmoid strip part 22. The cylindrical body part 21A of nearly one turn includes turned-up parts 23A, 24A at two points on the way between the outer periphery side contact part 30A and the inner periphery side contact part 40A. Each turned-up part 23A, 24A is to have a total length of the strip part 22 lengthened without having a diameter of the body part 21A enlarged. With this, the strip part 22 is free from plastic deformation exerting excellent spring characteristics, in case the contact member is pressed and squeezed till the inner periphery side contact part 40A comes in contact with the outer periphery side contact part 30A.