Contact

1. A contact comprising:

a first conductor that has a fitting hole formed therein;

a second conductor that has a shaft that can be inserted into the fitting hole and an annular groove formed on an outer circumference of the shaft; and

an inclined coil spring that has a ring inserted into a coil, is circularly formed by the ring to be provided inside the annular groove, and is in contact with the annular groove and the fitting hole to electrically connect the first and second conductors.

2. The contact according to claim 1 , wherein a size of an axial-direction width of a cross section of the ring is larger than a size of a radial-direction thickness.

3. The contact according to claim 2 , wherein

the inclined coil spring is helically wound in a shape of an ellipse and is provided inside the annular groove so that a long axis of the ellipse is directed to an axial direction of the shaft and a short axis is directed to a radial direction of the shaft, and

axial-direction both ends of the ring are in contact with a long-axis inner circumference of the inclined coil spring.

4. The contact according to claim 3 , wherein

the axial-direction end of the ring is formed in a shape of a hemicycle, and

a curvature radius of the hemicycle is smaller than a curvature radius of the long-axis inner circumference of the inclined coil spring.

5. The contact according to claim 3 , wherein

the annular groove is formed so that the more a width thereof approaches a bottom thereof and the more the width becomes narrow,

a gap is between the inclined coil spring and a bottom surface of the annular groove,

a top portion of the inclined coil spring is protruded from the annular groove, and

the inclined coil spring is in contact with a lateral surface of the annular groove to be caught in the annular groove.

6. The contact according to claim 5 , wherein a width size of a long-axis outer circumference of the inclined coil spring is smaller than a width size of an upper edge of the annular groove and is larger than a width size of the bottom of the annular groove.

7. The contact according to claim 1 , wherein the ring has a cut portion that is slanted to an axial direction of the shaft of the second conductor.

8. The contact according to claim 7 , wherein a circumferential-direction length of the cut portion of the ring is larger than a helically-wound pitch of the inclined coil spring.

9. The contact according to claim 7 , wherein the cut portion of the ring is shifted in a circumferential direction from a confronting position of both ends of the inclined coil spring and is arranged at a shifted position.

10. The contact according to claim 1 , wherein the ring is an insulating ring.

11. A contact comprising:

a first conductor with a fitting hole at an end thereof, a central axis of the fitting hole coincides with a central axis of the first conductor;

a second conductor with a shaft at one end thereof, the shaft provided with an annular groove formed on an outer circumference, the shaft configured to be inserted into the fitting hole of the first conductor; and

an inclined coil spring assembly including a rigid ring member configured to be inserted into a coil member, the coil member being held in a circular shape by the rigid ring when the rigid ring member is inserted into the coil member, the inclined coil spring assembly configured to be arranged inside the annular groove in the second conductor, and the first conductor and the second conductor configured to be in electrical contact via the inclined coil spring assembly when the inclined coil spring assembly is arranged inside the annular groove and the shaft of the second conductor is inserted into the fitting hole of the first conductor.