Connector for Flat Conductor

A second terminal includes a base portion extending along a bottom surface of a fitting chamber from a side of an opening of the fitting chamber toward a depth wall. The base portion includes a fixed piece fixed to the bottom surface and a movable piece that turns on the fixed piece as the turning fulcrum in a direction away from the bottom surface. The second terminal utilizes the total length of a spring piece portion and the movable piece as the spring length for elastically displacing a contact part.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a connector that connects a flat conductor to a substrate or the like.

2. Description of the Related Art

A connector for a flat conductor is used to conductively connect a flat conductor serving as a connection object member to a circuit of a substrate. For example, a so-called card edge connector (see Japanese Unexamined Patent Application Publication No. 9-306606) is used to connect a flat conductor formed by a hard substrate such as a memory card, an IC card, or a graphic board. In such a card edge connector (hereinafter simply referred to as “connector”), after a flat conductor is obliquely inserted into a fitting chamber of a housing, it is turned on an inserted leading edge so as to be parallel with a mounting board of the connector. Thus, contact portions of the flat conductor come into conductive contact with contact portions of terminals projecting in the fitting chamber to achieve connection between boards.

Such a connector for a flat conductor has a problem in that the inserting/removing force is large. For example, there is a flat conductor having 200 or more poles like a graphic board. When the number of poles of the flat conductor is large in this way, the number of terminals of the connector is also large. This increases the number of contact portions required to be bent when the flat conductor is inserted. Hence, insertion and removal of the flat conductor into and from the connector are tightened, and operability deteriorates. The number of terminals tends to increase as the function of an information processing apparatus, such as a computer, is diversified and sophisticated and the number of signals to be processed by the board increases. Hence, the need to reduce the inserting/removing force for the flat conductor is growing in the field of card edge connectors.

SUMMARY OF THE INVENTION

The present invention has been made in the context of the related art described above, and an object of the invention is to reduce the force for inserting and removing a flat conductor into and from a connector for the flat conductor.

To achieve the above object, the present invention is configured as follows.

A connector for a flat conductor according to an aspect of the present invention includes a housing having a fitting chamber for the flat conductor and a terminal to be in conductive contact with the flat conductor inserted in the fitting chamber. The terminal includes a base portion extending along a bottom surface of the fitting chamber from an open side of the fitting chamber to a depth side of the fitting chamber, and a spring piece portion having a contact part to be in conductive contact with the flat conductor inserted in the fitting chamber and extending from the base portion above the bottom surface. The base portion includes a fixed piece fixed to the bottom surface on the open side and a movable piece configured to turn on an end portion of the fixed piece on the depth side in a direction away from the bottom surface.

According to this structure, the terminal includes the base portion extending along the bottom surface of the fitting chamber and the spring piece portion extending above the bottom surface and having the contact part, and the spring piece portion is entirely raised from the bottom surface of the fitting chamber to function as a spring for elastically supporting the contact part. Moreover, in the present invention, the base portion of the terminal extending along the bottom surface of the fitting chamber has the movable piece that turns on the end portion of the fixed piece on the depth side in the direction away from the bottom surface. The movable piece functions as the spring for elastically supporting the contact part. Therefore, the sum of the length of the movable piece along the bottom surface of the fitting chamber and the length of the spring piece portion extending above the bottom surface can be utilized as the length of the spring for elastically displacing the contact part. Hence, according to this structure, the terminal can be softly displaced. This reduces the insertion force for the flat conductor and enhances operability of connection of the flat conductor.

Preferably, the spring piece portion has a first bent part bent from an end portion of the movable piece on the depth side toward the open side, and the first bent part serves as a turning fulcrum on which the contact part turns in sliding contact with the flat conductor toward the open side of the fitting chamber when the contact part is displaced toward the base portion by being pressed by the flat conductor inserted in the fitting chamber.

According to this structure, the contact part that is displaced toward the base portion by being pressed by the flat conductor is not simply displaced by being pushed down toward the base portion, but can be turned on the first bent part serving as the turning fulcrum toward the open side of the fitting chamber. Therefore, the distance of sliding contact of the contact part with the flat conductor can be made longer by a superposition effect of the turn of the movable piece of the base portion and the turn of the first bent part toward the open side of the fitting chamber than when the base portion is entirely fixed to the bottom surface. Hence, according to this structure, a substance attached to the flat conductor can be wiped off over a wide range. This enhances reliability of connection to a flat conductor having a large number of poles.

The spring piece portion may further include an extending part extending from the first bent part toward the open side and a second bent part bent from an end portion of the extending part on the open side toward the depth side to be connected to the contact part.

According to this structure, since the length of the extending part and the length of the second bent part can be utilized as the spring length, the spring length from the movable piece of the base portion to the contact part increases, and the terminal can softly touch the flat conductor. This can reduce the insertion force for the flat conductor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A connector for a flat conductor according to an embodiment of the present invention will be described below with reference to the drawings. In the description of the embodiment, a card edge connector is given as an example of a connector for a flat conductor. A flat conductor to be connected is a hard substrate P1.

In the specification, the claims, and the drawings, a width direction, a front-rear direction, and a height direction of a card edge connector1illustrated inFIG. 1(hereinafter simply referred to as “connector1”) are respectively taken as an X-direction, a Y-direction, and a Z-direction. A top surface and a bottom surface in the height direction Z are taken as an “upper” surface and a “lower” surface, respectively. Further, a front surface and a rear surface in the front-rear direction Y are taken as a “front” surface and a “rear” surface, respectively. Such definitions of upper, lower, front, and rear do not limit the mounting direction and use direction of the connector of the embodiment.

Structure of Connector1(FIGS.1to5)

The connector1includes a housing2that extends long in the width direction X. The housing2has an upper wall2a,right and left side walls2b,a bottom wall2c,and a rear wall2dthat are rectangular.

In an inner side surface of the upper wall2aof these walls, first-terminal attachment grooves2a1to which first terminals3are attached are provided along the front-rear direction Y of the connector1(FIG. 3). The adjacent first terminals3are arranged while being structurally isolated by a partitioning wall2a2that defines the first-terminal attachment grooves2a1. Similarly, second-terminal attachment grooves2c1to which second terminals4are attached are provided in the bottom wall2c.The adjacent second terminals4are arranged while being structurally isolated by a partitioning wall2c2that defines the second-terminal attachment grooves2c1. The connector1of the embodiment has230first terminals3and230second terminals4. For this reason, the connector1is configured as a multipole connector in which the insertion force of the hard substrate P1is likely to be large.

Inside the housing2, a fitting chamber2eis provided. In the fitting chamber2e,the hard substrate P1is inserted into conductive connection with the first terminals3and the second terminals4. The fitting chamber2eis formed by an inner space surrounded by inner walls of the housing2. Specifically, the fitting chamber2eis formed as an inner space surrounded by inner side surfaces of the upper wall2a,the side walls2b,the bottom wall2c,and the rear wall2ddescribed above.

On a front side of the fitting chamber2e,an opening2e1is provided as an insertion hole for the hard substrate P1serving as the flat conductor. On a depth side (rear side) of the fitting chamber2e,a depth wall2e2is provided as an inner side surface of the rear wall2d.On a front inner side surface of the upper wall2athat defines the fitting chamber2e,an insertion guide surface2a3is provided to guide insertion of the hard substrate P1. Groove bottom faces of the above-described second-terminal attachment grooves2c1form a bottom surface2e5of the fitting chamber2e.

The fitting chamber2eis divided into an upper fitting chamber2e3and a lower fitting chamber2e4according to the difference in depth from the opening2e1. The upper fitting chamber2e3is provided as an accommodating space for the hard substrate P1in a fitted state. The lower fitting chamber2e4is provided as a displacement space for the second terminals4to be described later, and is deeper toward the depth side of the fitting chamber2e(toward the depth wall2e2) than the upper fitting chamber2e3so that a long spring length can be ensured.

As illustrated in the external view ofFIG. 4, each of the first terminals3includes a substrate connecting portion3ato be soldered to a mounting board P2, a vertical piece portion3bextending along the height direction of the rear wall2dof the housing2, a horizontal piece portion3cextending frontward from the vertical piece portion3b,and a contact portion3dbent downward from a front end of the horizontal piece portion3c.

The first terminal3is inserted in the corresponding first-terminal attachment groove2a1from the rear side of the rear wall2dof the housing2, and is fixed by press-fitting at a fixed part3c1provided as a side projection on the horizontal piece portion3c.

As illustrated in the external view ofFIG. 5, each of the second terminals4includes a substrate connecting portion4ato be soldered to the mounting board P2, a vertical piece portion4bextending in the height direction on the front side of the housing2, a base portion4cextending rearward from the vertical piece portion4b,and a spring piece portion4dextending upward from the base portion4c.

The base portion4cis disposed in the corresponding second-terminal attachment groove2c1of the housing2. The base portion4chas a projection-like fixed piece4c1to be fixed to the second-terminal attachment groove2c1. A movable piece4c2continuously extends from the fixed piece4c1. The movable piece4c2turns on a connecting portion to the fixed piece4c1in a direction away from the bottom surface2e5of the fitting chamber2e.Since the base portion4cis disposed with the fixed piece4c1and the movable piece4c2in contact with the bottom surface2e5of the fitting chamber2e,the total height of the connector1is kept down. For example, if the base portion4cis raised from the bottom surface2e5, the height of the spring piece portion4din the upward direction is increased, and the total height of the housing2becomes large. However, such a problem is not caused in the embodiment.

The spring piece portion4dis provided as a spring extending upward from the bottom surface2e5of the fitting chamber2e.The spring piece portion4dis S-shaped in side view, as illustrated inFIG. 5. Specifically, the spring piece portion4dincludes, in order from the lower side, a first bent part4d1bent from the movable piece4c2toward the opening2e1of the fitting chamber2e,an extending part4d2extending from an end portion of the first bent part4d1toward the opening2e1, a second bent part4d3bent from an end portion of the extending part4d2close to the opening2e1toward the depth side of the fitting chamber2e,and a contact part4d4to be in conductive contact with a contact portion of the hard substrate P1.

In this way, the spring piece portion4densures a large spring length by connecting the first bent part4d1and the second bent part4d3, which are bent to face each other, by the extending part4d2. Since the movable piece4c2can also function as a spring, the spring length is further increased. Thus, the contact part4d4can be softly displaced, and this reduces the insertion force for the hard substrate P1.

As viewed from the front side, the right and left side walls2bare provided with fixing metals5to be soldered to the mounting board P2.

Fitting of Hard Substrate P1in Connector1(FIGS.6to9)

Next, a description will be given of a method for fitting the hard substrate P1in the connector1. Before the hard substrate P1is fitted, the connector1is mounted on the mounting board P2, as illustrated inFIG. 6.

As illustrated inFIG. 7, the hard substrate P1is obliquely inserted from the opening2e1of the fitting chamber2e.The hard substrate P1is pressed by the spring piece portion4dof each second terminal4, is guided by the insertion guide surface2a3, and is inserted into the fitting chamber2euntil its leading end comes into contact with the depth wall2e2.

At this time, the contact part4d4of the second terminal4is turned and displaced to move toward the opening2e1of the fitting chamber2efrom the state ofFIG. 6to the state ofFIG. 7, as shown by a solid line and a two-dot chain line inFIG. 9A. First, this is caused because the second bent part4d3is turned and displaced downward toward the opening2e1on the first bent part4d1when the contact part4d4is pressed downward by the hard substrate P1. Secondly, this is caused because the movable piece4c2is turned and displaced upward on the fixed piece4c1in the direction away from the bottom surface2e5of the fitting chamber2e.

The contact part4d4can be turned and displaced in sliding contact with the hard substrate P1toward the opening2e1of the fitting chamber2eby a superposition effect of these two turns. At this time, since the contact part4d4can be turned and displaced by utilizing the sum of the lengths of the spring piece portion4dand the movable piece4c2as the spring length, the second terminal4is softly displaced. This reduces the insertion force for the hard substrate P1and enhances connection operability.

As illustrated inFIG. 9B, an excellent wiping effect is also exerted because a distance d1for which the contact part4d4is in sliding contact with the hard substrate P1can be increased by the above-described two turns. That is,FIG. 9Bcompares the contact part4d4(solid line) when the movable piece4c2is turned and displaced and the contact part4d4(two-dot chain line) when the movable piece4c2is not turned and displaced in the state in which the hard substrate P1is inserted. When the movable piece4c2shown by the solid line is turned and displaced, the contact part4d4turns toward the opening2e1. Hence, the distance d1of sliding contact with the hard substrate P1can be made longer by a distance d3than a distance d2when the movable piece4c2shown by the two-dot chain line is not turned and displaced. Therefore, in the connector1, when a foreign substance, such as substrate residues, is attached to the hard substrate P1, the contact part4d4can wipe off the foreign substance over a wide range along the length direction (fitting direction) of the terminal of the hard substrate P1. Hence, high reliability of contact with the hard substrate P1can be obtained.

Next, the hard substrate P1is turned from the inserted state ofFIG. 7to the horizontal state ofFIG. 8. At this time, the hard substrate P1presses the contact part4d4to turn and displace the movable piece4c2until the movable piece4c2comes into contact with the bottom surface2e5of the fitting chamber2e,and also presses the contact portion3dof the first terminal3upward. Thus, the hard substrate P1is brought into conductive contact with the first terminal3and the second terminal4.

In the fitting state in which the hard substrate P1is turned to the horizontal position, the contact position of the contact part4d4with the hard substrate P1is returned by a distance d4from the contact position shown by the solid line inFIGS. 7 and 9Btoward the leading end of the hard substrate P1, as illustrated inFIG. 9C. In this case, the effective fitting length is a distance d5. Therefore, when the hard substrate P1is inserted, as illustrated inFIG. 9B, the contact part4d4can exert the wiping effect beyond the contact position in the fitting state ofFIG. 9C. Therefore, the contact part4d4can achieve highly reliable conductive contact by contact with the contact surface of the hard substrate P1from which the foreign substance has already been removed by wiping.

Modification of Embodiment

The movable piece4c2of the base portion4cis in contact with the bottom surface2e5of the fitting chamber2ein the state in which the above-described connector1of the embodiment is not fitted to the hard substrate P1. However, the movable piece4c2may be separate from the bottom surface2e5beforehand by being inclined with respect thereto.

While the connector1of the embodiment is disposed so that the contact portion3dprojects in the fitting chamber2ebeyond an extension line of the insertion guide surface2a3of the upper wall2a(seeFIG. 9A), it can be provided not to cross the extension line. In the case in which the contact portion3dis located beyond the extension line of the insertion guide surface2a3, when the hard substrate P1is inserted along the insertion guide surface2a3, it touches the contact portion3dand needs to be inserted while pressing and displacing the contact portion3d.This increases the insertion force. However, when the contact portion3dis disposed not to project into the fitting chamber2ebeyond the extension line of the insertion guide surface2a3of the upper wall2a,even when the hard substrate P1is inserted along the insertion guide surface2a3, it does not touch the contact portion3d.Hence, the hard substrate P1can be inserted with light force.

While the number of poles of the connector1of the above-described embodiment is 230, it may be other numbers as long as the connector is required to reduce the insertion force for bending a plurality of terminals during insertion and removal of the flat conductor. However, in the connector1of the present invention, the terminals can be softly bent by using the total length of the spring piece portion4dand the movable piece4c2as the spring length, as described above. Since this can reduce the insertion force for the flat conductor, the connector becomes more effective as long as the number of terminals increases.