Board mounting terminal

1. A board mounting terminal extending like a rod:

(a) for being inserted into a through-hole in a circuit board and being soldered to the circuit board,

(b) having a tip portion, and

(c) having a recessed groove in a face of the board mounting terminal:

(1) extending in a direction of extension of the board mounting terminal,

(2) having a tip end in the tip portion of the board mounting terminal, and

(3) having an area of a recess of the recessed groove in a cross-section extending in a direction transverse to the direction of extension of the board mounting terminal decreasing as a distance from the tip portion of the board mounting terminal, oriented in a direction of insertion of the board mounting terminal, increases.

2. The board mounting terminal according to claim 1 , wherein the recessed groove has at least one of:

(a) a width of the recessed groove, and

(b) a depth of the recessed groove

appearing in the cross-section decreasing continuously as the distance from the tip portion of the board mounting terminal increases.

3. The board mounting terminal according to claim 2 , wherein:

(a) the recess in the cross-section is triangular in shape, and

(b) the recessed groove has both:

(1) a length of a base of the triangle, and

(2) a height of the triangle

decreasing continuously as the distance from the tip portion of the board mounting terminal increases.

4. The board mounting terminal according to claim 1 , wherein the area of the recess of the recessed groove decreases stepwise in cross-section in sequence as the distance from the tip portion board mounting terminal increases.

5. The board mounting terminal according to claim 1 , wherein:

(a) the board mounting terminal has a rectangular shape in the cross-section when the recessed groove is filled up,

(b) the recessed groove is in a first face of the board mounting terminal, and

(c) the board mounting terminal has a second recessed groove in a second face of the board mounting terminal opposite the first face of the board mounting terminal.

6. The board mounting terminal according to claim 1 , wherein the recessed groove is longer than the thickness of the circuit board.

7. The board mounting terminal according to claim 1 , wherein the recessed groove has a triangular shape.

8. The board mounting terminal according to claim 1 , wherein the recessed groove has a rectangular shape.

9. The board mounting terminal according to claim 1 , wherein the recessed groove has a U-like shape.

10. The board mounting terminal according to claim 1 , wherein the recessed groove has a semicircular shape.

11. The board mounting terminal according to claim 1 , wherein the board mounting terminal has a plurality of faces and selected faces of the board mounting terminal have the recessed grooves.

12. The board mounting terminal according to claim 1 , wherein the board mounting terminal has a plurality of faces with each face of the board mounting terminal having the recessed groove.

13. The board mounting terminal according to claim 8 , wherein the board mounting terminal has a plurality of faces and selected faces of the board mounting terminal have the recessed grooves.

14. The board mounting terminal according to claim 9 , wherein the board mounting terminal has a plurality of faces and selected faces of the board mounting terminal have the recessed grooves.

15. The board mounting terminal according to claim 10 , wherein the board mounting terminal has a plurality of faces and selected faces of the board mounting terminal have the recessed grooves.