Interface structure
An interface structure connecting an electronic component to a circuit board. The interface structure includes a base defining an elongated through hole with a central axis and a coil spring retained in the elongated through hole. The coil spring has a proximal portion and a distal portion extending from the elongated through hole in an uncompressed condition and being offset at an angle with respect to the central axis. As the coil spring is compressed, the coil spring creates a force having a component substantially perpendicular to the central axis.
1. An interface structure for connecting an electronic component to a circuit board, the interface structure comprising:
a base defining an elongated through hole;
a coil spring retained in the elongated through hole, the coil spring having:
a proximal portion;
a distal portion; and
an intermediate portion extending between the proximal portion and the distal portion,
wherein the distal and intermediate portions have a same external diameter,
wherein, when the coil spring is an uncompressed condition, the distal portion is inclined at an angle θ>0° with respect to a central axis of the intermediate portion of the coil spring, and
wherein the distal portion extends outside the elongated through hole so that as the coil spring is compressed, the coil spring creates a force having a component substantially perpendicular to the central axis.
2. The interface structure of claim 1 , wherein the elongated through hole has an upper portion and a lower portion, the upper portion having a relatively larger diameter than the lower portion,
wherein the proximal portion is closely wound with a relatively larger diameter than the intermediate and distal portions, the respective diameters of the proximal and intermediate portions being sized comparably to fit within the upper and lower portions of the elongated through hole, respectively.
3. The interface structure of claim 1 , wherein the upper portion and lower portion of the elongated through hole form a transitional step portion for supporting the coil spring when a contact pin is inserted into the coil spring.
4. The interface structure of claim 1 , wherein the coil spring buckles when compressed.
5. The interface structure of claim 1 , wherein the base is fabricated from an electrically isolative material, the coil spring is conductive, and the elongated through hole has a conductive plating on an inner wall of the elongated through hole.
6. The interface structure of claim 1 , further comprising an intermediate plate having a second through hole aligned with the elongated through hole for guiding a contact pin into the coil spring.
7. The interface structure of claim 6 , wherein the intermediate plate also retains the coil spring in the elongated through hole.
8. The interface structure of claim 7 , wherein the second through hole has a smaller diameter than an upper portion of the elongated through hole for retaining the coil spring.
9. The interface structure of claim 1 , wherein the base defines a plurality of elongated through holes, and wherein a coil spring is in each of the plurality of elongated through holes.
10. The interface structure of claim 1 , wherein the electronic component comprises a socket.
11. The interface structure of claim 1 , wherein the angle θ is in a range of 10° to 20°.
12. The interface structure of claim 11 , wherein the angle θ is 15°.