Electrical connector having a mechanism for supplementing spring ...

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ELECTRICAL CONNECTOR HAVING A
MECHANISM FOR SUPPLEMENTING
SPRING CHARACTERISTICS OF A
CONTACT

This invention claims priority to prior Japanese patent application JP 2003-134207, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates to an electrical connector for connecting a substrate as a mother board and a connection object as a daughter board.

For example, Japanese Patent Application Publication (JP-A) No. H6-196230 (corresponding to U.S. Pat. No. 5,273,450) discloses an electrical connector for connecting a mother board and a daughter board. The electrical connector comprises a connector body mounted on the mother board, and a compressible connector element carried by the connector body. The daughter board is inserted into the connector body and disposed to be substantially perpendicular to the mother board. The daughter board is provided with a circuit element to be electrically connected to the connector element. The connector element is used as a contact for electrically connecting the mother board and the daughter board to each other.

In recent years, the electrical connector of the type is required to be reduced in size. However, if the electrical connector is reduced in size, the contact is also miniaturized. It is therefore difficult to provide the contact with sufficient spring characteristics. This results in permanent deformation of the contact or insufficiency in contact force, thereby decreasing a contact reliability.

SUMMARY OF THE INVENTION

It is therefore an object of this invention to provide an electrical connector which is capable of supplementing spring characteristics of a contact so as to improve a contact reliability of the contact even if the contact is reduced in size.

It is another object of this invention to provide an electrical connector which is easy to make design change for adjusting spring characteristics of a contact and to carry out replacement of parts.

According to this invention, there is provided an electrical connector comprising an insulating housing, a conductive contact held by the housing, an operating member for applying a pressing force to the contact to bring the contact into contact with a connection object, and an elastic member elastically deformable and interposed between the operating member and the contact.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of an electrical connector according to one embodiment of this invention together with a connection object;

FIG. 2 is a plan view of the electrical connector illustrated in FIG. 1;

FIG. 3 is an exploded perspective view of the electrical connector illustrated in FIG. 1 together with the connection object;

FIG. 4 is a front view showing a shaft portion of an actuator of the electrical connector illustrated in FIG. 1;

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FIG. 5 is a perspective view showing a cam portion of an operating member of the electrical connector illustrated in FIG. 1;

FIG. 6 is a front view showing a state where the electrical 5 connector illustrated in FIG. 1 is attached to each of upper and lower ends of the connection object; and

FIG. 7 is a right side view of the electrical connectors and the connection object illustrated in FIG. 6 together with two base boards.

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DESCRIPTION OF THE PREFERRED
EMBODIMENT

Referring to FIGS. 1 through 3, description will be made 15 of an electrical connector according to one embodiment of this invention.

The electrical connector 1 illustrated in the figure is generally called a card-edge electrical connector and comprises an insulating housing 11, a plurality of conductive 20 contacts 21 disposed within the housing 11, and a plurality of contact moving mechanisms 50 coupled to the housing 11.

The housing 11 comprises a frame member 12 and a plurality of (four in the illustrated example) header members

25 13 fixed to the frame member 12 and aligned in a single line. The frame member 12 has a pair of first frame portions 15 extending in a longitudinal direction of the housing 11 and facing the header members 13 with a space kept therefrom in a transversal direction of the housing 11, and a pair of

30 second frame portions 17 connecting longitudinal opposite ends of the first frame portions 15. Thus, a combination of the first and the second frame portions 15 and 17 surrounds the header members 13.

Each of the header members 13 has a header base portion

35 13a mounted on a base board 41 as a mother board, such as a printed circuit board, a header holding portion 13fc extending from a center of the header base portion 13a upward in a vertical direction, and a pair of contact holding portions 13c formed integral on left and right sides of the header base

40 portion 13a, respectively. The header holding portion 13fc has an upper surface provided with an object receiving portion 13d for receiving an end portion of a connection object 31 as a daughter board, such as a printed circuit board, and holding the connection object 31 in the vertical direc

45 tion. In FIG. 1, the vertical direction is a direction perpendicular to a center line C.

Each of the header members 13 has a pair of bearing portions 13/formed as grooves. The bearing portions 13/are positioned on left and right sides of the header base portion

50 13a above the contact holding portions 13c.

In FIG. 1, the contacts 21 and the contact moving mechanisms 50 are provided on left and right sides of a virtual plane containing the center line C and perpendicular to a drawing sheet, respectively. Each of the contacts 21 has a

55 holding portion 21a held by the contact holding portion 13c, a contact spring portion 21b extending upward from one end of the holding portion 21a, and a terminal portion 21c extending outward from the contact holding portion 13c. The contact spring portion 21b extends upward from the one

60 end of the holding portion 21a along each of a pair of vertical side surfaces of the header holding portion 13fc.

As will later become clear, each of the contact moving mechanisms 50 serves to move each of the contacts 21 in a first direction A (FIG. 1) to bring the contact 21 into contact

65 with the connection object 31 and to move the contact 21 in a second direction B (FIG. 1) opposite to the first direction A to separate the contact 21 from the connection object 31. 3

Thus, the contact 21 is moved by the contact moving mechanism 50 between a contact position and a non-contact position where the contact 21 is in contact with and out of contact from the connection object 31, respectively.

Referring to FIGS. 4 and 5 in addition to FIGS. 1 through 5 3, each of the contact moving mechanisms 50 will be described.

As shown in FIG. 1, the contact moving mechanism 50 comprises an actuator 51 held by the bearing portion 13/, an operating member 61 located at a predetermined position on 10 an inner wall surface 15a of the first frame portion 15 to move the actuator 51, and an elastic member, i.e., an auxiliary spring member 71 elastically deformable and interposed between the actuator 51 and the operating member 61. The auxiliary spring member 71 is a leaf spring formed by 15 bending a band-like spring material into a generally rectangular cylindrical shape.

The first frame members 15, the contacts 21, the actuators 51, the operating members 61, and the auxiliary spring members 71 are disposed symmetrical with respect to the 20 above-mentioned virtual plane. Each of the actuators 51 has a pressing portion 51a to be brought into contact with the contact spring portion 21b of the contact 21, and a cylindrical shaft portion 51fc removably engaged with the bearing portion 13/of the header member 13 so that the actuator 51 25 is movable in the first and the second directions A and B.

The operating member 61 is held on the inner wall surface 15a of the first frame portion 15. The operating member 61 has a cam portion 63 for moving the actuator 51 in the first and the second directions A and B. The operating member 61 30 is kept in contact with the auxiliary spring member 71 so as to be rotatable in sliding contact with the auxiliary spring member 71.

The contact spring portion 21b of the contact 21 is provided with a butt portion 21d formed at its intermediate 35 position and butted to the pressing portion 51a of the actuator 51. The butt portion 21d is slightly bent towards the pressing portion 51a so as to be butted to the pressing portion 51a of a flat shape. The contact spring portion 21b has a free end provided with a contact point 21/protruding 40 towards the above-mentioned virtual plane to face the connection object 31.

The cam portion 63 has a first cam surface 63a for applying a pressing force to the auxiliary spring member 71 and a second cam surface 63fc for releasing the pressing 45 force upon the auxiliary spring member 71. The first cam surface 63a presses the auxiliary spring member 71 to move the actuator 51 in the first direction A. The second cam surface 63fc releases the pressing force upon the auxiliary spring member 71 to allow the actuator 51 to move in the 50 first direction B by a spring restoring force of the contact spring portion 21b.

The inner wall surface 15a of the first frame portion 15 is provided with a recess 15fc having a cylindrical surface. The auxiliary spring member 71 has a deformable plate portion 55 71a facing the inner wall surface 15a of the first frame portion 15 and a pair of spring holding portions 71b extending from opposite ends of the deformable plate portion 71a and bent and folded back to face the deformable plate portion 71a. The spring holding portions 71b has end 60 portions engaged with and held by a pair of spring receiving portions 51c formed on the actuator 51.

The first cam surface 63a is an outer peripheral surface having a cylindrical shape and adapted to be brought into contact with the deformable plate portion 71a of the auxil- 65 iary spring member 71. The second cam surface 63fc is a flat surface formed by linearly cutting the first cam surface 63a

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in directions intersecting with each other. The recess 15fc of the first frame portion 15 receives a part of the outer peripheral surface of the operating member 61, i.e., a part of the first cam surface 63a.

When the first cam surface 63a faces the auxiliary spring member 71, the auxiliary spring member 71 is pressed by the first cam surface 63a to move the actuator 51 in the first direction A. At this time, the contact spring portion 21b is energized or urged. On the other hand, when the second cam surface 63fc faces the auxiliary spring member 71, the auxiliary spring member 71 is not substantially pressed and, as a consequence, the actuator 51 is moved in the second direction B under the restoring force of the contact spring portion 21b.

As best shown in FIGS. 2 and 3, a plurality of partition walls lie are formed between the first frame portions 15 at predetermined intervals in the longitudinal direction of the housing 11 to define four chambers llg in which the header members 13 are accommodated, respectively. Between the first frame portions 15, a space is left in the transversal direction of the housing 11 so that the actuator 51 and the auxiliary spring member 71 are movably accommodated in order to allow the contacts 21 held by the header member 13 to be moved and displaced.

For convenience of illustration, only one actuator 51 is shown in FIG. 3. However, each of the four header members 13 holds two actuators 51. Specifically, the shaft portion 51fc of each of the actuators 51 is inserted into the bearing portion 13/of the header member 13 so that the actuator 51 is rotatable. Thus, each of the chambers llg separated by the partition walls lie accommodates one header member 13 provided with the contacts 21 and two actuators 51 provided with the auxiliary spring members 71.

The frame member 12 is provided with a pair of through holes 11/ corresponding to the recesses 15fc of the first frame portions 15 and extending in a longitudinal direction. Thus, the through holes 11/ are disposed on left and right sides of the above-mentioned virtual plane, respectively. In each through hole 11/, the operating member 61 is inserted to be rotatable. The operating member 61 has a cylindrical part of a long size extending in the longitudinal direction and, therefore, can be inserted into or removed from the through hole 11/.

Each of the partition walls lie has an upper surface provided with a cut portion 11m formed at a center position between the first frame portions 15 to receive the end portion of the connection object 31. Each of the second frame portions 17 has an upper surface provided with a cut portion 17m formed at a center position between the first frame portions 15 to receive the end portion of the connection object 31. After the header members 13 are mounted on the base board 41, the frame member 12 is fixed to the base board 41.

The connection object 31 has a plurality of positioning protrusions 31c. The positioning protrusions 31c are inserted into the cut portions 11m and 17m to properly position the connection object 31.

The terminal portion 21c of each contact 21 is soldered and connected to a conductive portion (conductive pad) 41a formed on the base board 41 and connected to a circuit on the base board 41. The first and the second frame portions 15 and 17 are fixed to the base board 41 by screws 81 inserted through bottom surfaces of the cut portions 11m and 17m.

Next, an operation of connecting the connection object 31 to the electrical connector 1 will be described with reference to FIG. 1. In FIG. 1, the contact moving mechanism 50 on the left side of the center line C is at a position in a released