BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a perspective view showing an embodiment of the connector according to the present invention;
FIG. 2A is a plan view of the connector according to the invention shown in FIG. 1;
FIG. 2B is an elevation view of the connector according to the invention shown in FIG. 1;
FIG. 2C is a side view of the connector according to the invention shown in FIG. 1;
FIG. 3 shows a contact state between the connector according to the invention and upper and lower wiring boards;
FIG. 4 shows a contact state between the lower wiring board and a pair of contacts according to the invention, which are formed by using metallic resilient members;
FIG. 5 shows an example of the contact according to the invention;
FIG. 6 is a cross-sectional view showing an assembled state of an insulator and the contact according to the invention which is disposed in a through-hole formed in the insulator;
FIG. 7A and FIG. 7B show a contact which has two resilient contact arms that are put in two-point contact with an associated electrode; and
FIG. 8A to FIG. 8G are an exploded view of a silicone rubber connector which electrically connects upper and lower wiring boards 76 and 77.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 and FIGS. 2A to 2C show an embodiment of a connector 10 according to the present invention. FIG. 1 is a perspective view of the connector according to the embodiment of the invention. FIG. 2A is a plan view of the connector of the invention shown in FIG. 1. FIG. 2B is an elevation view of the connector of the invention shown in FIG. 1. FIG. 2C is a side view of the connector of the invention shown in FIG. 1.
An insulator 11 serves as a connector housing which is formed of, e.g. a synthetic resin such as plastics. A plurality of through-holes 12, which penetrate the insulator 11 in a vertical direction in the Figures, are formed in the insulator 11 in a linear arrangement. As shown in FIG. 2A, opening portions 24 of the through-holes 12 are arranged in a linear fashion on an upper surface 42 of the insulator 11.
A pair of contacts 13 and 13′, which are formed of electrically conductive resilient members, are inserted and fixed in parallel in each of the through-holes 12. Electric contact portions 14 are formed on an upper part and a lower part of each contact 13, 13′. The electric contact portions 14 come in contact with associated electrode portions (i.e. contact lands) of an upper wiring board 15 and a lower wiring board 20 (see FIG. 3) (an associated lower electrode of the upper wiring board 15 is not shown).
As shown in FIG. 2B, first bosses 17 each having a large diameter and projecting upward of the insulator 11 are formed at right and left end portions of the insulator 11. The first bosses 17 can be used for alignment between the insulator 11 and the lower wiring board 20. In addition, as shown in FIG. 2B, second bosses 18 each having a small diameter and projecting downward of the insulator 11 are formed at the right and left end portions of the insulator 11. The second bosses 18 can be used for alignment between the insulator 11 and the upper wiring board 15.
As shown in FIG. 2A, a small-diameter boss receiving hole 21 is formed in each of the large-diameter first bosses 17. A small-diameter boss projecting from a lower part of another insulator (not shown), which is disposed above the insulator 11, can be inserted in the small-diameter boss receiving hole 21. In a case where a plurality of wiring boards are stacked via a plurality of connectors 10, small-diameter second bosses 18 of an upper connector 10 (not shown) are inserted in the small-diameter boss receiving holes 21 of the first bosses 17 of a lower connector 10. Thereby, the connectors 10 can precisely be aligned. Examples of the wiring boards 15 and 20 include a board having wiring on its surface, a board on which multi-layer wiring is formed, a board including circuit components such as semiconductor components, and a board including electronic modules such as a display device and a switch device.
In general, a frame (not shown) having an inner wall surrounding the insulator 11 can be disposed around the insulator 11, thereby to mechanically reinforce and protect the insulator 11. For example, refer to the frame 83 shown in FIG. 8C. The insulator 11 can be put in resilient contact with the inner wall of the frame 83 by a plurality of springs 19 (see FIG. 2B) formed on both end portions of the insulator 11, and can thus be fixed.
FIG. 3 shows a connection state between the connector 10 and the upper wiring board 15 and lower wiring board 20. It is understood that FIG. 3 shows some of the mounted components of the embodiment which includes, for example, a plurality of wiring boards and a plurality of connectors. FIG. 3 shows two wiring boards 15 and 20 alone, but a large number (e.g. ten) of wiring boards may be stacked in actual use via a plurality of connectors 10.
Electrode portions 23, which are arranged on the upper surface of the upper wiring board 15, are electrodes for contact with contact portions of a connector (not shown) which is disposed above the upper wiring board 15. As shown in FIG. 3, boss insertion holes 22 are formed in the upper wiring board 15 and lower wiring board 20. The boss insertion holes 22 are used for alignment between the connector 10 and the wiring board 15, 20.
FIG. 4 shows a contact state between the lower wiring board 20 and a pair of contacts 13 which are formed by using metallic resilient members. FIG. 4 shows the state in which the insulator 11 and other pairs of contacts are removed. FIG. 4 shows an example of use in which a pair of contacts, which have the same shape, are disposed in opposite directions. The present invention is not limited to the use of the paired contacts having the same shape.
In FIG. 4, the paired contacts 13 and 13′ are disposed vertically in parallel to each other. The paired contact portions 14 at the lower parts of the contacts 13 and 13′ are put in resilient contact with the same electrode portion 16 formed on the surface of the lower wiring substrate 29. Thus, even if a fault occurs in one of the contacts 13, normal signal transmission is enabled by the other contact 13′. In order to keep good contact with the electrode portion 16, the contact surfaces 14 of the contacts 13 and 13′ should preferably be formed as rolled surfaces, and not as broken surfaces.
FIG. 5 shows an example of the contact 13 that is used in this embodiment. The shape of the contact 13, which is shown in FIG. 5, can be obtained by punching a thin metal plate or by subjecting it to a lithography process. The contact surface 14 is formed by bending itself in a rearward direction of the sheet surface of FIG. 5, for example, in a substantially U shape as shown in FIG. 4. This structure can increase the contact area of the contact surface 14 with the electrode portion formed on the surface of the board 15. By adopting this structure, the contact surface 14 can be formed as a rolled surface, and not as a broken surface.
In this invention, the shape of the contact is not limited to the example shown in FIG. 5. It should suffice if the contact is formed of a resilient member and has at least two contact surfaces which come in electrical contact with associated electrode portions (contact lands) formed on the two opposed wiring boards.
A vertically extending columnar portion 27 of the contact 13 of the embodiment shown in FIG. 5 includes a hook-shaped engaging portion 25 and a projection-shaped engaging portion 26 for engaging the contact 13 with the inner wall of the insulator 11. Thereby, the contact 13 can surely be fixed on the inner wall of the insulator 11.
In addition, as shown in FIG. 5, strip-shaped portions 28, which extend in up-and-down directions in a meandering fashion to the upper and lower contact portions 14, may be formed at middle parts of the columnar portion 17. Each strip-shaped portion 28 may include a U-shaped portion 30 which extends in a horizontal direction, and a U-shaped portion 31 which extends in a vertical direction. By virtue of such meandering portions, flexible and exact contact is realized between the contact 13 and the electrode portions 16 of the wiring boards.
FIG. 6 shows a cross section taken along line Y-Y′ in FIG. 2. FIG. 6 shows the inside of the through-hole 12 formed in the insulator 11 and the contact 13 that is inserted and fixed in the through-hole 12. A groove portion 36, which constitutes an engaging portion for engaging the hook-shaped engaging portion 25 of the contact 13 and restricting downward movement of the contact 13, is formed in an upper part of the inner wall 35 of the insulator 11. In addition, an engaging portion 40 having a projection portion 38, which is mated with the projection-shaped engaging portion 26 of the contact 13, is formed in the through-hole 12.
The paired contacts 13 are disposed such that they are separated by a predetermined distance by a partial partition wall 41 within the through-hole 12. In this embodiment, two contacts are disposed in the through-hole 12. Alternatively, three contacts, for instance, may be disposed in the through-hole 12.
In the present invention, at least two contacts are disposed at mutually opposed positions in each of the plural through-holes 12 of the insulator 11. Thus, the engaging portion with the insulator can be disposed at a position separated from the contact portion, and the contact may include a resilient portion and a vertically bent portion of the contact portion which extends from that separated position. By virtue of this structure, even if the contacts are disposed at mutually opposed positions, their contact portions may be arranged in two rows on the same line.
The embodiment of the invention has been described above. However, the invention is not limited to the embodiment, and various modifications may be made, as needed.
Patent Application
20080057748
