WO2009143252A1

WO2009143252A1 - Sheet-like electrical connector

Info

Publication number: WO2009143252A1
Application number: PCT/US2009/044688
Authority: WO
Inventors: Toshihiro Niitsu
Original assignee: Molex Incorporated
Priority date: 2008-05-20
Filing date: 2009-05-20
Publication date: 2009-11-26
Also published as: JP5236354B2; JP2009283182A

Abstract

An electrical connector (1) is disclosed. The electrical connector (1) is disposed between a pair of electronic devices (100A,100B) so as to electrically couple them, comprising multiple conductive elastic bodies (50) each including a dielectric body (51) having elasticity; a central conductor portion (54) formed in the dielectric body (51) along a thickness direction of the dielectric body (51) for conducting electricity between a front surface and a back surface of the dielectric body (51); and an outer conductor portion (53) formed in the dielectric body (51) so as to surround the central conductor portion (54) for conducting electricity between the front surface and the back surface of the dielectric body (51). Further included is a frame (11) for retaining each of the multiple conductive elastic bodies (50).

Description

SHEET-LIKE ELECTRICAL CONNECTOR

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The Present Invention relates to a sheet-like electrical connector disposed between a pair of electronic devices so as to connect them.

DESCRIPTION OF THE RELATED ART

Conventionally, electrical connectors may be disposed between two electronic devices, such as circuit boards, and held between conductor portions of the electronic devices so as to electrically connect the two electronic devices. Such electrical connectors are generally referred to as sheet-like connectors. An example of this type of electrical connector is disclosed in Japanese Patent Publication No. UM-A-05-55553. According to this disclosure, the sheet-like connector is disposed between a probe card installed in a semiconductor wafer test apparatus and a test circuit board. This electrical connector is further provided with an elastomer, which is a rubber-like elastic body, and conductor portions are formed in the thickness direction of the elastomer. Further, in order to match the impedance of an electric transmission line, each conductor portion has a coaxial structure having a central conductor portion and an outer conductor portion surrounding the central conductor portion.

However, in the conventional sheet-like electrical connector, numerous conductor portions are formed inside one elastic body. Hence, the electrical connector has a problem in which the position of each conductor portion is apt to deviate from its proper position (that is, so that it may align with a terminal of the electronic device). In other words, in order to form numerous conductor portions inside one elastic body, it is necessary to make the area of the elastic body relatively large. However, when a large elastic body is further extended by heat or an external force, the relative positions of the conductor portions formed inside the elastic body are apt to change, and the conductor portions are apt to deviate from their proper positions. SUMMARY OF THE INVENTION

The Present Invention has been developed in view of and to overcome at least the above- mentioned disadvantage, and therefore has an object of providing an electrical connector, disposed between a pair of electronic devices, capable of restraining change in the relative position of each conductor portion disposed thereon. To solve the above-mentioned disadvantage, the Present Invention provides a sheet-like electrical connector disposed between a pair of electronic devices so as to electrically couple them. The electrical connector preferably comprises multiple conductive elastic bodies, each conductive elastic body including a dielectric body having elasticity; a central conductor portion formed in the dielectric body along a thickness direction of the dielectric body for conducting electricity between a front surface and a back surface of the dielectric body; and an outer conductor portion formed in the dielectric body so as to surround the central conductor portion for conducting electricity between the front surface and the back surface of the dielectric body. Further included in the electrical connector is a frame for retaining each conductive elastic body. Since the conductive elastic bodies are retained by the frame, it is possible to restrain the change in the relative position of each conductive elastic body. As a result, the positions of the central conductor portion and the outer conductor portion, which are formed in one conductive elastic body, can be restrained from changing relative to the positions of the central conductor portion and the outer conductor portion formed in another conductive elastic body.

BRIEF DESCRIPTION OF THE FIGURES

The organization and manner of the structure and operation of the Present Invention, together with further objects and advantages thereof, may best be understood by reference to the following Detailed Description, taken in connection with the accompanying Figures, wherein like reference numerals identify like elements, and in which:

Figure 1 is an exploded perspective view showing an electrical connector according to an embodiment of the Present Invention, and circuit boards electrically coupled to each other via the electrical connector;

Figure 2 is an enlarged perspective view showing the electrical connector; Figure 3 is a sectional view showing the electrical connector and the circuit boards, taken along the Line III-III of Fig. 2; Figure 4 is a perspective view showing a conductive elastic body provided for the electrical connector;

Figure 5 is a side view showing the conductive elastic body;

Figure 6 is a sectional view taken along the Line VI-VI of Fig. 5; Figure 7 is an enlarged perspective view showing a frame provided for the electrical connector;

Figure 8 is a sectional view taken along the Line VIII-VIII of Fig. 7; and

Figure 9 is an enlarged plan view showing the circuit board, and illustrating an example of conductor patterns of the circuit board.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the Present Invention may be susceptible to embodiment in different forms, there is shown in the Figures, and will be described herein in detail, specific embodiments, with the understanding that the discussion herein is to be considered an exemplification of the principles of the Present Invention, and is not intended to limit the Present Invention merely to that as illustrated. Further, in the embodiments illustrated in the Figures, representations of directions such as up, down, left, right, front, rear and the like, used for explaining the structure and movement of the various elements of the Present Invention, are not absolute, but relative. These representations are appropriate when the elements are in the position shown in the Figures. If the description of the position of the elements changes, however, it is assumed that these representations are to be changed accordingly.

Preferably, sheet-like electrical connector 1 is disposed between a pair of electronic devices so as to electrically couple those devices. As illustrated in Figs. 1 and 3, electrical connector 1 is disposed between circuit boards 10OA, 10OB. As illustrated in Fig. 2, electrical connector 1 preferably includes multiple conductive elastic bodies 50, for conducting electricity between the surfaces of electrical connector 1, and frame 11, for retaining multiple conductive elastic bodies 50. As illustrated, each conductive elastic body 50 is preferably arranged on the same plane with one another. Further, frame 11 retains each conductive elastic body 50 at positions which correspond to conductor portions 101 of circuit boards 10OA, 10OB. As illustrated in Figs. 4 and 6, each conductive elastic body 50 includes conductor portion 52 and dielectric body 51. Dielectric body 51 is preferably made of a dielectric material having elasticity and formed into a disc shape. Concave portion 5 Ih is formed on the outer circumferential surface of dielectric body 51. Convex portion 12a, formed on the inner circumferential surface of circular retention hole 12 in frame 11 (see Fig. 3), is fitted into concave portion 5 Ih upon assembly, whereby each conductive elastic body 50 is retained inside one of circular retention holes 12.

Preferably, electrical connector 1 is a high-speed transmission connector for transmitting high-frequency signals, and conductor portion 52 of each conductive elastic body 50 has a coaxial structure to match the impedance of an electric transmission line. In other words, conductor portion 52 has central conductor portion 54, serving as a signal conductor and having a cylindrical shape, and outer conductor portion 53, serving as a ground conductor and having a tubular shape. Central conductor portion 54 is preferably formed in dielectric body 51 so as to be oriented along the thickness (Z) direction of dielectric body 51, whereby electricity is conducted between front and back surfaces 51a, 51b thereof. Outer conductor portion 53 is preferably formed in dielectric body 51 so as to surround central conductor portion 54 and also be oriented along the thickness direction of dielectric body 51. The diameter of outer conductor portion 53 preferably depends on the impedance of electrical connector 1 required to match the impedance of the electric transmission line between circuit boards 10OA, 10OB.

Additionally, dielectric body 51 preferably has a diameter corresponding to that of outer conductor portion 53. More specifically, the outside diameter of dielectric body 51 is slightly larger than the outside diameter of outer conductor portion 53. Dielectric body 51 also has outer circumferential portions 5 Ij, 51k surrounding outer conductor portion 53 and making contact with the outer circumferential surface of outer conductor portion 53. Outer circumferential portions 51j, 51k are each formed into a thin annular shape (see Fig. 6). Further, in the example given herein, one central conductor portion 54 and one outer conductor portion 53 are formed for each conductive elastic body 50.

As illustrated in Fig. 6, central conductor portion 54 and outer conductor portion 53 pass through dielectric body 51, and end portions 54a, 54b, 53a, 53b are exposed from front surface 51a and back surface 51b of dielectric body 51, respectively. In particular, in each conductive elastic body 50, end portion 54a of central conductor portion 54 and end portion 53a of outer conductor portion 53 are positioned above front surface 51a of dielectric body 51, and end portion 54b of central conductor portion 54 and end portion 53b of outer conductor portion 53 are positioned below the back surface of dielectric body 51. Additionally, inner annular portions 5 Id, 5 Ie surrounding end portions 54a, 54b of central conductor portion 54 are provided on both front and back surfaces 51a, 51b of dielectric body 51. Further, outer annular portions 51f, 51g are provided on both front and back surfaces 51a, 51b of dielectric body 51 along the inner circumferential surfaces of end portions 53a, 53b of outer conductor portion 53.

Electrical connector 1 is disposed between circuit boards 10OA, 10OB, and conductor portions 101 of circuit boards 10OA, IOOB are pressure- welded to each conductive elastic body 50 (see Fig. 3). As illustrated in FIG. 9, signal conductor pattern 101a and ground conductor patterns 101b, 101c, 101d, serving as conductor portions 101, are provided on the surface of circuit board IOOA facing electrical connector 1. Conductor patterns 101a, 101b, 101c, 101d constitute one group corresponding to one conductive elastic body 50. Ground conductor patterns 101b, 101c, 101d are provided on the circumference having a diameter approximately identical with that of outer conductor portion 53, and signal conductor pattern 101a is positioned inside the circumference. Preferably, signal conductor pattern 101a is pressure- welded to central conductor portion 54, and ground conductor patterns 101c, 101d and lOle are pressure- welded to outer conductor portion 53. Conductor patterns similar to those of circuit board IOOA are also formed on the surface of circuit board IOOB facing electrical connector 1, and each pattern is pressure- welded to central conductor portion 54 or outer conductor portion 53. Note that conductor patterns 101a, 101b, 101c, 101d illustrated in Fig. 9 are an example of conductor patterns, and other conductor patterns may be provided on circuit board IOOA.

Preferably, central conductor portion 54 and outer conductor portion 53 can each be made of metal filler particles, and arranged in the thickness direction and mutually connected, for example. Central conductor portion 54 and outer conductor portion 53 can be formed in the dielectric body 51 using a known method, i.e., in which metal filler particles are blended with the original material of dielectric body 51 and then arranged using a magnetic field toward the thickness direction of conductive elastic body 50.

Frame 11 is preferably made of an insulating material having higher stiffness than that of dielectric body 51, and formed into a rectangular plate shape. As illustrated in Fig. 7, multiple circular retention holes 12 are formed in frame 11. The inside diameter of each circular retention hole 12 corresponds to the outside diameter of each conductive elastic body 50, and each conductive elastic body 50 is retained inside each circular retention hole 12. Hence, the relative positions of multiple conductive elastic bodies 50 are secured (see Fig. 3). Further, convex and concave surfaces are respectively formed on the inner circumferential surface of each circular retention hole 12 and the outer circumferential surface of dielectric body 51. These surfaces are fitted into each other, whereby conductive elastic body 50 is retained inside circular retention hole 12. Particularly, as shown in Figs. 7 or 8, convex surface 12a, protruding toward the center in the radial direction of circular retention hole 12, is formed on the inner circumferential surface of circular retention hole 12. Further, convex portion 12a has an annular shape and is formed in the circumferential direction of circular retention hole 12 on the inner circumferential surface thereof. On the other hand, concave portion 5 Ih, depressed toward the center in the radial direction, is preferably formed on the outer circumferential surface of dielectric body 51, as illustrated in Figs. 5 or 6. Concave portion 51h is also formed in the circumferential direction of dielectric body 51 on the outer circumferential surface thereof. And, as illustrated in Fig. 3, convex portion 12a is fitted into concave portion 5 Ih, whereby each conductive elastic body 50 is retained inside circular retention hole 12. Each conductive elastic body 50 is preferably elastically deformed and fitted into circular retention hole 12. That is, when each conductive elastic body 50 is fitted into circular retention hole 12, outer circumferential fringe 5 Ii of dielectric body 51 slightly shrinks, climbs over convex portion 12a of circular retention hole 12, and then elastically returns, whereby conductive elastic body 50 is retained inside. However, the structure for retaining conductive elastic body 50 inside circular retention hole 12 is not limited to this structure. A concave portion may be formed on an inner surface of circular retention hole 12, and a convex portion may be formed on a side surface of dielectric body 51, for example.

Each conductive elastic body 50 is preferably formed to be thicker than frame 11. Hence, end portion 54a of central conductor portion 54 and end portion 53a of outer conductor portion 53 are both positioned above the front surface of frame 11. Further, end portion 54b of central conductor portion 54 and end portion 53b of outer conductor portion 53 are positioned below the back surface of frame 11, as illustrated in Fig. 3.

Each conductive elastic body 50 is retained at a position corresponding to conductor portions 101 of circuit boards 10OA, IOOB using frame 11. In this structure, as illustrated in Figs. 1 or 2, multiple conductive elastic bodies 50 are disposed so as to be arranged in multiple rows (e.g., four rows along the X direction). Further, as illustrated in Fig. 2, multiple conductive elastic bodies 50 are disposed in an oblique lattice-like manner such that each conductive elastic body 50 is positioned in an oblique (D) direction with respect to conductive elastic bodies 50 of the adjacent rows. In other words, in the direction (Y) passing through the midpoint position P between two adjacent conductive elastic bodies 50 in the same row and being perpendicular to the row, the centers of conductive elastic bodies 50 in the adjacent rows are positioned.

As illustrated in Figs. 7 8, between two adjacent circular retention holes 12 in the same row, connecting portion 1 Ib, the thickness of which is smaller than that of the other portion of frame 11, is formed. Each circular retention hole 12 is partitioned from adjacent circular retention holes 12 using connecting portion lib. As described above, convex portion 12a is formed into an annular shape so as to protrude inward from the inner circumferential surface of circular retention hole 12. Further, two adjacent retention holes 12 in the same row are disposed such that their outermost fringes are tangent to each other. Still further, part of convex portion 12a of two adjacent circular retention holes 12 serves as connecting portion 1 Ib for partitioning therefrom. Hence, multiple circular retention holes 12 partitioned from each other can be disposed at positions as close as possible thereto.

In addition, as illustrated in Fig. 1, frame 11 has multiple fastening portions 13 for securing the circuit boards 10OA, IOOB thereto. Preferably, fastening portions 13 are formed at the fringes of frame 11 and are positioned on the diagonal line thereof. Each fastening portion 13 is preferably a rivet and has protruding portions 13a, 13b protruding upward and downward from frame 11, as illustrated in Figs. 2 or 7. In circuit board 10OA, holes 102A are formed at positions corresponding to the positions of fastening portions 13, and in the circuit board IOOB, holes 102B are formed at positions corresponding to the positions of fastening portions 13. Protruding portions 13a, 13b of fastening portions 13 are fitted into holes 102A, 102B. Then, the ends of protruding portions 13a, 13b are provided caulking while circuit boards 10OA, IOOB are pressed on electrical connector 1, whereby circuit boards 10OA, IOOB are respectively secured to electrical connector 1 (see Fig. 3). Note that Fig. 3 illustrates a state in which the ends of protruding portions 13a, 13b are deformed by caulking.

As described above, electrical connector 1 includes multiple conductive elastic bodies 50, each having dielectric body 51 having elasticity, central conductor portion 54 formed in dielectric body 51 in the thickness direction thereof for conducting electricity between front surface 51a and back surface 51b, and outer conductor portion 53 formed in dielectric body 51 so as to surround central conductor portion 54 for conducting electricity between front surface 51a and back surface 51b. Further, each conductive elastic body 50 is retained using frame 11. In this embodiment, it is possible to suppress the change in the relative position of each conductive elastic body 50. As a result, the position of central conductor portion 54 and outer conductor portion 53, which are formed in conductive elastic body 50, can be restrained from changing relative to the position of central conductor portion 54 and outer conductor portion 53, which are formed in another conductive elastic body 50.

In addition, frame 11 has a plate shape in which multiple circular retention holes 12 are formed, and multiple conductive elastic bodies 50 are retained inside circular retention holes 12, respectively. With this configuration, each conductive elastic body 50 can be retained using a simple structure. Further, each conductive elastic body 50 is elastically deformed and fitted into circular retention hole 12 of frame 11. With this configuration, each conductive elastic body 50 can be further securely retained inside retention hole 12. Moreover, frame 11 includes fastening portions 13 for securing a pair of electronic devices (e.g., circuit boards 10OA, 100B) to frame 11. With this configuration, circuit board IOOA can be connected to circuit board IOOB using electrical connector 1.

While a preferred embodiment of the Present Invention is shown and described, it is envisioned that those skilled in the art may devise various modifications without departing from the spirit and scope of the foregoing Description and the appended Claims. For example, one conductor portion 52 is formed in one dielectric body 51 in the above description. However, it is also be possible to have a configuration in which multiple conductor portions 52 are formed in one dielectric body 51 and conductive elastic bodies having multiple conductor portions 52 are retained using the frame. Further, in the above description, multiple conductive elastic bodies 50 are retained in an oblique lattice-like manner using frame 11. However, the positions of conductive elastic bodies 50 are not limited thereto, but may be changed appropriately depending on positions of conductor portions of the electronic devices to be connected to electrical connector 1. Still further, although a rivet is used as fastening portion 13 in the above description, the fastening portion is not limited thereto, but a bolt or the like may also be used.

Claims

CLAIMSWHAT IS CLAIMED IS:

1. An electrical connector disposed between a pair of electronic devices 10OA, IOOB so as to electrically couple the electronic devices 10OA, IOOB, the electrical connector comprising: multiple conductive elastic bodies 50, each conductive elastic body 50 including: a dielectric body 51; a central conductor portion 54 formed along a thickness direction of the dielectric body 51; and an outer conductor portion 53 formed in the dielectric body 51 so as to surround the central conductor portion 54; and a frame 11 for retaining each conductive elastic body 50.

2. The electrical connector of Claim 1, wherein the dielectric body 51 has elasticity.

3. The electrical connector of Claim 2, wherein the central conductor portion 54 is adapted to conduct electricity between a front surface and a back surface of the dielectric body 51.

4. The electrical connector of Claim 3, wherein the outer conductor portion 53 is adapted to conduct electricity between the front surface and the back surface of the dielectric body 51.

5. The electrical connector of Claim 4, wherein the frame 11 defines a plate shape in which multiple circular retention holes 12 are formed.

6. The electrical connector of Claim 5, wherein each conductive elastic body 50 are retained inside the circular retention holes 12 of the frame 11.

7. The electrical connector of Claim 6, wherein each conductive elastic body 50 is elastically deformed and fitted into one of the circular retention holes 12 of the frame 11.

8. The electrical connector of Claim 4, wherein the frame comprises fastening portions 13.

9. The electrical connector of Claim 8, wherein the fastening portions 13 are adapted to secure at least one of the pair of electronic devices 10OA, IOOB to the frame 11.