Connector assembly

The invention relates to a connector assembly.

Conventionally, there is proposed an electrical connection structure with low height, formed by fitting together a first connection member formed of a flexible print circuit (flexible printed wiring board) and a second connection member (e.g., Japanese Patent Number 4059522).

The first connection member includes a thin insulator film having flexibility as a substrate, and pads having elasticity and electrical conductivity are formed on a surface of the insulator film. The insulator film is provided with through holes which are pierced in the insulator film within the pads in a thickness direction thereof. The pads are each provided with their own pinholes communicating with the through holes.

On the other hand, the second connection member is provided with conductive protrusions, each of which is shaped like a column, at positions thereof facing the pads of the first connection member. The conductive protrusions are each adapted to be inserted into the pinholes of the pads.

When the first connection member is connected with the second connection member, the conductive protrusions are inserted into the pinholes of the pads, so that the pads are bent in an insertion direction of the conductive protrusions and are in elastic contact with the conductive protrusions by the restoring forces of the pads.

In the aforementioned electrical connection structure, the conductive protrusions are inserted into the pinholes of the pads, and thereby the pads are put into a condition of being bent in the insertion direction of the conductive protrusions into the pinholes. Here, there is a problem that excessive stress concentration occurs when the pads are connected with the conductive protrusions, because all the pads are made of electrically conducting material such as metal.

The present invention has been achieved in view of the above circumstances, and an object thereof is to provide a connector assembly capable of reducing stress occurring in spring part for electrical connection and fit holding.

In order to solve the above problem, a connector assembly ( 1 ) of the present invention comprises a female connector ( 10 ) and a male connector ( 20 ). The female connector ( 10 ) comprises a film substrate ( 11 ) and a pad ( 12 ). The film substrate ( 11 ) is made from insulating material to be shaped like a thin board with flexibility, and comprises a through hole ( 14 ) pierced in the film substrate in a thickness direction thereof. The pad ( 12 ) has electrical conductivity and is formed around the through hole ( 14 ) on a surface of the film substrate ( 11 ). The male connector ( 20 ) comprises a conductive protrusion ( 22 ) adapted to be inserted into the through hole ( 14 ) to be electrically connected to the pad ( 12 ). The film substrate ( 11 ) comprises a slot ( 15 ) that is formed to extend along a plane of the film substrate ( 11 ) with one end side thereof connected to the through hole ( 14 ). The film substrate ( 11 ) comprises part ( 17 ) without the pad ( 12 ). The part ( 17 ) is placed at least part of a region, on the surface of the film substrate ( 11 ), which is present at other end side of the slot ( 15 ) and free to be bent by the conductive protrusion ( 22 ).

In an embodiment, the conductive protrusion ( 22 ) of the male connector ( 20 ) comprises a head ( 24 ) at a tip side thereof, and the head ( 24 ) has a cross section larger than that of a base side of the conductive protrusion ( 22 ). The pad ( 12 ) is adapted to climb over the head ( 24 ) to come into contact with the base side of the conductive protrusion ( 22 ).

In an embodiment, the male connector ( 20 ) comprises a combining protrusion ( 22 B) adapted to be inserted into a combining through hole ( 14 B) provided in the film substrate ( 11 ) to be mechanically combined with the combining through hole ( 14 B).

In the present invention, the part ( 17 ) without the pad ( 12 ) is placed at a region which is present at the other side of the slot ( 15 ) and free to be bent by the conductive protrusion ( 22 ). The part ( 17 ) without the pad ( 12 ) in the film substrate ( 11 ) is easy to bend in comparison with a region with the pad ( 12 ). It is therefore possible to reduce stress occurring in spring part (i.e., peripheral part of the through hole ( 14 ) in the film substrate ( 11 )) for electrical connection and fit holding, because a stress occurring when the conductive protrusion ( 22 ) is inserted into the through hole ( 14 ) is reduced by the peripheral part of the through hole ( 14 ) being bent by the conductive protrusion ( 22 ).

Preferred embodiments of the invention will now be described in further details. Other features and advantages of the present invention will become better understood with regard to the following detailed description and accompanying drawings where:

FIG. 1A is a perspective view of a socket of a connector assembly in accordance with an embodiment of the present invention, and FIG. 1B is a transverse sectional view of the socket;

FIG. 2A is a perspective view of the connector assembly with the socket separated from a header of the connector assembly, and FIG. 2B is a perspective view of the connector assembly with the socket combined with the header;

FIG. 3A is a side view of the socket, and FIG. 3B is a side view of the header;

FIG. 4 is a plan view of the header;

FIG. 5 illustrates main parts of the connector assembly and shows a combination state of the connector assembly;

FIG. 6 is a perspective view of the connector assembly in an example of use; and

FIG. 7A is a plan view of a connection pad of the socket, and FIG. 7B is a plan view of a combining pad of the socket.

As shown in FIGS. 2 and 3 , a connector assembly 1 in accordance with an embodiment of the present invention includes a socket (a female connector) 10 and a header (a male connector) 20 , which are configured to be mechanically and electrically connected with each other.

In the embodiment, the socket 10 is disposed in a first side of a first direction (an upper side in an example of FIG. 2A ), while the header 20 is disposed in a second side of the first direction (a lower side in the example of FIG. 2B ). Therefore, in the embodiment, first and second surfaces of the socket 10 at the first and second sides of the first direction are upper and lower surfaces, respectively, and first and second surfaces of the header 20 at the first and second sides of the first direction are also upper and lower surfaces, respectively.

The socket 10 includes a film substrate 11 shaped like a rectangular board (or sheet) that is longer in a second direction perpendicular to the first direction, pads 12 made of electrically conducting material, and a reinforcing plate 13 shaped like a rectangular board that is longer in the second direction. The pads 12 include connection pads 12 A and combining pads 12 B.

In the embodiment, both ends of the film substrate 11 in a third direction perpendicular to the second direction are curved like a U so as to cover two longer sides of the reinforcing plate 13 .

The header 20 includes a header substrate 21 shaped like a rectangular board that is longer in the second direction, and posts 22 made from electrically conducting material. The posts 22 include connection posts 22 A and combining posts 22 B.

The structure of the header 20 is first explained with reference to FIGS. 2-4 .

The header substrate 21 is formed of a rigid substrate made from insulating material, such as an epoxy glass substrate (FR4) for example. The header substrate 21 is provided with the posts 22 protruded from a surface (an upper surface) of the header substrate 21 facing the socket 10 . Each post 22 is shaped like a column. The posts 22 include connection posts 22 A and combining posts 22 B.

Each connection post 22 A is made from electrically conducting material to be in the shape of a circular column of which cross section parallel to the upper surface of the header substrate 21 is circular in shape and substantially constant for the entire length thereof in a vertical direction (a second direction) perpendicular to the upper surface of the header substrate 21 (or the first direction). In the embodiment, the header 20 includes the connection posts 22 A in sets of two or more (e.g., two), and two or more sets of (e.g., ten sets of) connection posts 22 A are arranged on the upper surface of the header substrate 21 along two longer sides of the header substrate 21 five sets each so that all of the connection posts 22 A are spaced at predetermined intervals in the second and third directions. Specifically, each set of connection posts 22 A arranged in the second direction has two connection posts 22 A arranged apart from each other in the third direction so that all of the connection posts 22 A are arranged in a staggered (zigzag) array. In this arrangement, it is possible to reduce the surface area of a region where the connection posts 22 A are arranged, and also to comparatively widen intervals among adjacent connection posts 22 A.

The combining posts 22 B are arranged on the upper surface of the header substrate 21 at both sides thereof in the second direction one each so that the ten sets of connection posts 22 A intervene between the combining posts 22 B. In other words, the connection posts 22 A are arranged in a staggered array in a region intervening between the two combining posts 22 B on the upper surface of the header substrate 21 in the second direction. Each combining post 22 B is placed around the center of the upper surface of the header substrate 21 in the third direction.

Each combining post 22 B includes a neck 23 that is shaped like a column and protruded from the upper surface of the header substrate 21 , and a head 24 that is continuously formed on a tip of the neck 23 . A size (a diameter) of the head 24 is larger than that of the neck 23 . Each of the neck 23 and the head 24 is circular in cross section parallel to the upper surface of the header substrate 21 , and a size (a diameter) of the cross section of the head 24 is larger than that of the neck 23 . That is, the head 24 at the tip side of the combining post 22 B is larger than the neck 23 at the base side thereof, and thereby the combining post 22 B is shaped like somehow a mushroom. The head 24 is tapered so as to become gradually narrower from a bottom side of the head 24 to an end face side thereof.

A protrusion length of each combining post 22 B from the upper surface of the header substrate 21 is set to be larger than that of each connection post 22 A. Each dimension of the connection posts 22 A and the combining posts 22 B is set so that each height of the necks 23 except for the heads 24 is larger than each height of the connection posts 22 A.

As shown in FIG. 4 , conductive patterns 25 , 26 are formed on the upper surface of the header substrate 21 . The conductive patterns 25 correspond to the connection posts 22 A, respectively, while the conductive patterns 26 correspond to the combining posts 22 B, respectively. Each connection post 22 A is formed in a corresponding conductive pattern 25 , and each combining post 22 B is formed in a corresponding conductive pattern 26 .

Each conductive pattern 25 is formed so as to connect a land 25 a that is shaped like a circle and placed at a position of a corresponding connection post 22 A, and an edge through hole (a via recess) 25 b that is formed at a longer side of the header substrate 21 nearer to the land 25 a . Each conductive pattern 26 is formed so as to connect a land 26 a that is shaped like a circle and placed at a position of a corresponding combining post 22 B, and two edge through holes (via recesses) 26 b that are formed at two corners, nearer to the land 26 a , of four corners of the header substrate 21 . The edge through holes 25 b , 26 b are formed by plating the sides of the header substrate 21 with electrically conducting material, and employed to mount the header substrate 21 on a circuit board 102 as shown in FIG. 6 for example.

The structure of the socket 10 is next explained with reference to FIGS. 1-3 .

The film substrate 11 is formed of a flexible substrate for assembling a flexible printed circuit (FPCB: flexible printed circuit board). The flexible substrate is made from insulating material (e.g., polyimide resin) to be shaped like a thin board (a sheet) having flexibility.

The film substrate 11 is provided with through holes 14 pierced in the film substrate 11 in the first direction (a thickness direction thereof). When the socket 10 is combined with the header 20 , the posts 22 are inserted into the through holes 14 , respectively. That is, the through holes 14 are placed at positions corresponding to the posts 22 , respectively. The through holes 14 are separated into 2 kinds and include a connection through hole 14 A placed at a position corresponding to each connection post 22 A and a combining through hole 14 B placed at a position corresponding to each combining post 22 B. The connection through holes 14 A are placed at the positions corresponding to the connection posts 22 A, respectively and are accordingly arranged in a staggered array like the connection posts 22 A. The combining through holes 14 B are formed in the film substrate 11 at both sides thereof in the second direction one each so that the connection through holes 14 A intervene between the combining through holes 14 B.

Each connection through hole 14 A is circular in shape and has a size (a diameter) slightly smaller than that of a corresponding connection post 22 A. The film substrate 11 includes slots 15 in sets of two or more (e.g., four), corresponding to each of the through holes 14 . For example, the slots 15 in the film substrate 11 are separated into 2 kinds and include a slot 15 A as an element of a set corresponding to each connection through hole 14 A and a slot 15 B as an element of a set corresponding to each combining through hole 14 B. Four slots 15 A corresponding to each connection through hole 14 A are pierced in the film substrate 11 in the first direction (the thickness direction thereof) and extend in the second and third directions from a corresponding connection through hole 14 A. Each slot 15 A, of which first end is connected to a corresponding connection through hole 14 A, becomes gradually wider in width from the first end to a second end thereof. That is, a connection through hole 14 A and four slots 15 A corresponding to each connection post 22 A constitute an opening shaped like a clover, of which sizes in the second and third directions are set to be larger than a size (a diameter) of a corresponding connection post 22 A.

Each combining through hole 14 B is circular in shape and has a size (a diameter) slightly smaller than that of the neck 23 of a corresponding combining post 22 B. Four slots 15 B corresponding to each combining through hole 14 B are pierced in the film substrate 11 in the first direction (the thickness direction thereof) and extend in the second and third directions from a corresponding combining through hole 14 B. Each slot 15 B, of which first end is connected to a corresponding combining through hole 14 B, becomes gradually wider in width from the first end to a second end thereof. That is, a combining through hole 14 B and four slots 15 B corresponding to each combining post 22 B constitute an opening shaped like a clover, of which sizes in the second and third directions are set to be larger than each size (diameter) of the neck 23 and the head 24 of a corresponding combining post 22 B.

The film substrate 11 further includes pads 12 , conductive patterns 16 , and pad-free parts 17 corresponding to the through holes 14 , respectively. For example, the pads 12 in the film substrate 11 are separated into 2 kinds and include a connection pad 12 A corresponding to each of the connection through holes 14 A (or the connection posts 22 A) and a combining pad 12 B corresponding to each of the combining through holes 14 B (or the combining posts 22 B). The conductive patterns 16 in the film substrate 11 are separated into 2 kinds and include a conductive pattern 16 A corresponding to each of the connection pads 12 A (or the connection through holes 14 A) and a conductive pattern 16 B corresponding to each of the combining pads 12 B (or the combining through holes 14 B). The pad-free parts 17 in the film substrate 11 are separated into 2 kinds and include a pad-free part 17 A corresponding to each of the connection pads 12 A (or the connection through holes 14 A) and a pad-free part 17 B corresponding to each of the combining pads 12 B (or the combining through holes 14 B). Each pad 12 A is formed by copper plating around a corresponding connection through hole 14 A on a surface (a second surface) of the film substrate 11 (a surface facing the header 20 ), and adapted to be electrically connected to a corresponding connection post 22 A. Each pad 12 A is placed on the whole of the periphery of the opening formed of corresponding connection through hole 14 A and slots 15 A, and is electrically connected to a corresponding conductive pattern 16 A on the second surface of the film substrate 11 . Each pad-free part 17 A is placed at least part of a region, on the second surface of the film substrate 11 , which is present at the second end side of a corresponding slot 15 A and free to be bent by a corresponding connection post 22 A. Specifically, two or more pad-free parts 17 A are placed at two or more locations of a region, on the second surface of the film substrate 11 , which are present at the second end sides of two or more slots 15 A connected to a corresponding connection through hole 14 A and free to be bent by a corresponding connection post 22 A. In the embodiment, four pad-free parts 17 A are placed at four locations of a region, on the second surface of the film substrate 11 , which are present at the second end sides of four slots 15 A connected to a corresponding connection through hole 14 A and free to be bent by a corresponding connection post 22 A. Each pad-free part 17 A exposes part of the second surface of the film substrate 11 .

Similarly, each pad 12 B is formed by copper plating around a corresponding combining through hole 14 B on the second surface of the film substrate 11 , and adapted to be electrically connected to a corresponding combining post 22 B. Each pad 12 B is placed on the whole of the periphery of the opening formed of corresponding combining through hole 14 B and slots 15 B, and is electrically connected to a corresponding conductive pattern 16 B. Each pad-free part 17 B is placed at least part of a region, on the second surface of the film substrate 11 , which is present at the second end side of a corresponding slot 15 B and free to be bent by a corresponding combining post 22 B. Specifically, two or more pad-free parts 17 B are placed at two or more locations of a region, on the second surface of the film substrate 11 , which are present at the second end sides of two or more slots 15 B connected to a corresponding combining through hole 14 B and free to be bent by a corresponding combining post 22 B. In the embodiment, four pad-free parts 17 B are placed at four locations of a region, on the second surface of the film substrate 11 , which are present at the second end sides of four slots 15 B connected to a corresponding combining through hole 14 B and free to be bent by a corresponding combining post 22 B. Each pad-free part 17 B exposes part of the second surface of the film substrate 11 . Note that if the combining posts 22 B are not used for electrical connection, the pads 12 B and the conductive patterns 16 B are unnecessary.

The pads 12 A, 12 B are made: of material having electrical conductivity and elasticity; and by forming copper patterns, having 9 μm in thickness, on the second surface of the film substrate 11 having electric non-conductance for example. Also, nickel or nickel alloy may be plated on surfaces of the copper patterns of the pads 12 A, 12 B.

The reinforcing plate 13 is, for example, made of nickel silver to be shaped like a rectangular board which has a length similar to that of the header substrate 21 in the second direction, and a width rather larger than that of the header substrate 21 in the third direction. The reinforcing plate 13 is pasted on a back of the surface of the film substrate 11 facing the header 20 . The reinforcing plate 13 has a length similar to that of the film substrate 11 in the second direction, and a width shorter than that of the film substrate 11 in the third direction. Accordingly, the film substrate 11 is pasted on the surface (second surface) of the reinforcing plate 13 , and remaining ends thereof ( 11 ) in the third direction are wrapped round the reinforcing plate 13 with the remaining ends turned around a back of the reinforcing plate 13 . Tip ends of the conductive patterns 16 A, 16 B are also turned around the back of the reinforcing plate 13 along with the remaining ends of the film substrate 11 .

The reinforcing plate 13 includes holes 130 . For example, the holes 130 are separated into 2 kinds and include a hole 13 A corresponding to each of the connection through holes 14 A and a hole 13 B corresponding to each of the combining through holes 14 B. Each hole 13 A has the same center as a corresponding connection through hole 14 A, and an inside dimension (an internal diameter) larger than that of the hole 14 A and an external dimension (an outer diameter) of a corresponding connection post 22 A so that the corresponding connection through hole 14 A is formed therein ( 13 A). Therefore, a connection pad 12 A placed on each periphery of the connection through holes 14 A is extended inward from the inner circumferential surface of a corresponding hole 13 A.

Each hole 13 B has the same center as a corresponding combining through hole 14 B, and an inside dimension (an internal diameter) larger than that of the hole 14 B and an external dimension (an outer diameter) of a corresponding combining post 22 B (head 24 ) so that the corresponding combining through hole 14 B is formed therein ( 13 B). Therefore, a combining pad 12 B placed on each periphery of the combining through holes 14 B is extended inward from the inner circumferential surface of a corresponding hole 13 B.

Accordingly, when the socket 10 is connected with the header 20 , the connection posts 22 A are inserted into the respective holes 13 A through the respective connection through holes 14 A, and the connection pads 12 A come into contact with respective peripheral surfaces of the posts 22 A, while the combining posts 22 B are inserted into the respective holes 13 B through the respective combining through holes 14 B, and the combining pads 12 B come into contact with respective peripheral surfaces of the necks 23 of the combining posts 22 B (see FIG. 5 ).

Each pad 12 is formed based on material and thickness dimension which are chosen and decided so as to have not only electrical conductivity but also elasticity (shape restoring force). Accordingly, elasticity is given to each of parts in which at least the pads 12 in the film substrate 11 are formed. That is, the film substrate 11 includes spring pieces 18 each of which is formed of part thereof ( 11 ) extended inward from the inner circumferential surface of a corresponding hole 130 . The spring pieces 18 are separated into 2 kinds and include a spring piece 18 A as an element of a set corresponding to each of the holes 13 A and a spring piece 18 B as an element of a set corresponding to each of the holes 13 B. Each pad 12 A is formed around tip ends of a corresponding set of (four) spring pieces 18 A, while each pad 12 B is formed around tip ends of a corresponding set of (four) spring pieces 18 B. The film substrate 11 includes at least part ( 17 ) without the pad 12 on the surface (the second surface) of the film substrate 11 . The part ( 17 ) without pad 12 is placed at least part of a region, on the surface of the film substrate 11 , which is present at other end side of the slot 15 (the other side thereof from the side connected to the through hole 14 ) and free to be bent by the post 22 . In the embodiment, each pad-free part 17 A corresponding to one connection through hole 14 A is present at the second end sides of two adjacent slots 15 A (or between them) and free to be bent by a corresponding connection post 22 A. Each pad-free part 17 B corresponding to one combining through hole 14 B is present at the second end sides of two adjacent slots 15 B (or between them) and free to be bent by a corresponding combining post 22 B. That is, each of the spring pieces 18 A is provided with a pad-free part 17 A with neither pad 12 A nor pad 12 B, and each of the spring pieces 18 B is provided with a pad-free part 17 B with neither pad 12 A nor pad 12 B. It is accordingly possible to improve each elasticity of the spring pieces 18 A, 18 B in comparison with the case where each pad 12 A is formed on the whole of a corresponding spring piece 18 A and each pad 12 B is formed on the whole of a corresponding spring piece 18 B.

Numerous modifications can be applied to each shape of the pad-free parts 17 A, 17 B of the spring pieces 18 A, 18 B with neither pad 12 A nor pad 12 B, and the shapes are not limited to the illustrated shapes. In the example of FIG. 1 , a pad-free part 17 A is placed around the center of a corresponding spring piece 18 A in a width direction thereof, and a connection pad 12 A is placed at each end of the spring piece 18 A in the width direction, but may be placed at other part of the spring piece 18 A. Similarly, a pad-free part 17 B is placed around the center of a corresponding spring piece 18 B in a width direction thereof, and a combining pad 12 B is placed at each end of the spring piece 18 B in the width direction, but may be placed at other part of the spring piece 18 B. For example, as shown in FIG. 7A , a pad-free part 17 A may be placed at each end of a corresponding spring piece 18 A in a width direction thereof. Similarly, as shown in FIG. 7B , a pad-free part 17 B may be placed at each end of a corresponding spring piece 18 B in a width direction thereof. It is also possible to improve each elasticity of the spring pieces 18 A, 18 B to prevent excessive stress concentration from occurring, as above. A connection pad 12 A placed at a tip of each spring piece 18 A is electrically connected with a ring shaped electric conductor 16 C placed in the outer circumference of corresponding slots 15 A through a conductive pattern formed on the center of the spring piece 18 A in a width direction thereof. Similarly, a connection pad 12 B placed at a tip of each spring piece 18 B is electrically connected with a ring shaped electric conductor 16 C placed in the outer circumference of corresponding slots 15 B through a conductive pattern formed on the center of the spring piece 18 B in a width direction thereof. Each conductor 16 C is electrically connected with a corresponding conductive pattern ( 16 A or 16 B).

As shown in FIG. 5 , when the socket 10 is electrically connected with the header 20 , each connection post 22 A comes into contact with the spring pieces 18 A around a corresponding connection through hole 14 A and is then inserted into the connection through hole 14 A while elastic deforming the spring pieces 18 A to widen the connection through hole 14 A. Spring pieces 18 A around each connection through hole 14 A press, by their elastic forces, a corresponding connection pad 12 A against the peripheral surface of a corresponding connection post 22 A. As a result, each connection post 22 A is electrically connected with a corresponding connection pad 12 A. Similarly, each combining post 22 B comes into contact with the spring pieces 18 B around a corresponding combining through hole 14 B and is then inserted into the combining through hole 14 B while elastic deforming the spring pieces 18 B to widen the combining through hole 14 B. Spring pieces 18 B around each combining through hole 14 B press, by their elastic forces, a corresponding combining pad 12 B against the peripheral surface of the neck 23 of a corresponding combining post 22 B. As a result, each combining post 22 B is electrically connected with a corresponding combining pad 12 B.

Each connection post 22 A is substantially constant in outer diameter for the entire length thereof in the first direction (the vertical direction), and has no protrusion like each combining post 22 B. Therefore, each connection post 22 A has no part hooked to a corresponding connection pad 12 A when being inserted into a corresponding connection through hole 14 A, and accordingly hardly contributes to mechanical connection between the socket 10 and the header 20 . On the other hand, each combining post 22 B is shaped like a mushroom so that the head 24 at a tip side thereof is larger than the neck 23 at a base side thereof. Accordingly, when the socket 10 is connected to the header 20 , spring pieces 18 B corresponding to each combining through hole 14 B climb over the head 24 of a corresponding combining post 22 B to come into contact with the neck 23 of the combining post 22 B. Therefore, the tips of spring pieces 18 B around each combining through hole 14 B are hooked to the head 24 of a corresponding combining post 22 B, thereby providing retainer of the above combining post 22 B along with the head 24 to mechanically connect the socket 10 and the header 20 . As an example, each connection post 22 A may be shaped like a mushroom in the same way as each combining post 22 B. In this case, it is possible to connect the socket 10 and the header 20 through the connection posts 22 A.

When the socket 10 is withdrawn from the header 20 , each combining post 22 B is withdrawn from a corresponding combining through hole 14 B while elastic deforming spring pieces 18 B around the hole 14 B to widen the hole 14 B. At this time, the tips of spring pieces 18 B around each combining through hole 14 B hooks to a head 24 of a corresponding combining post 22 B, but if the strength for withdrawing the socket 10 from the header 20 is relatively large, the above spring pieces 18 B elastic deform and then the tips thereof climb over the above head 24 . As a result, each combining post 22 B is withdrawn from a corresponding combining through hole 14 B. On the other hand, each connection post 22 A is shaped like a column that is substantially constant in outer diameter for the entire length thereof in the vertical direction (the second direction). Therefore, when the socket 10 is withdrawn from the header 20 , spring pieces 18 A around each connection through hole 14 A do not hook to a corresponding connection post 22 A. As a result, the above spring pieces 18 A can be easily withdrawn from a corresponding connection through hole 14 A.

That is, when combining the socket 10 with the header 20 , a user has only to align each through hole 14 with a corresponding post 22 and then press the film substrate 11 against the header substrate 21 from above (from the upper side as shown in FIG. 5 ). As a result, each connection post 22 A is inserted into a corresponding connection through hole 14 A to be electrically connected to a corresponding connection pad 12 A. In addition, each combining post 22 B is inserted into a corresponding combining through hole 14 B to be electrically connected to a corresponding combining pad 12 B, thereby electrically connecting the socket 10 and the header 20 . The tips of spring pieces 18 B around each combining through hole 14 B are hooked to the head 24 of a corresponding combining post 22 B, thereby providing retainer of the above combining post 22 B along with the head 24 to mechanically connect the socket 10 and the header 20 .

When withdrawing the socket 10 from the header 20 , a user has only to move the film substrate 11 upward from the header substrate 21 . As a result, each combining post 22 B is withdrawn from a corresponding connection through hole 14 B and then the socket 10 is mechanically disconnected from the header 20 . In addition, each connection post 22 A is withdrawn from a corresponding connection through hole 14 A, while each combining post 22 B is withdrawn from a corresponding combining through hole 14 B, and thereby each pad 12 ( 12 A, 12 B) is separated from a corresponding post 22 ( 22 A, 22 B). Therefore, the socket 10 is electrically disconnected from the header 20 .

As shown in FIG. 6 , the connector assembly 1 in the embodiment is used to mechanically and electrically connect two circuit boards. In the example of FIG. 6 , the socket 10 is mounted on a circuit board 101 formed of a flexible print circuit (a flexible printed wiring board), while the header 20 is mounted on a circuit board 101 formed of a rigid substrate. Therefore, if the socket 10 is combined with the header 20 , the two circuit boards 101 , 102 are electrically and mechanically connected with each other. The conductive patterns 16 A, 16 B of the socket 10 are joined to conductive patterns 103 of the circuit board 101 with solder, and thereby the socket 10 is mounted on the circuit board 101 . The edge through holes 25 b , 26 b of the header 20 are joined to conductive patterns (not shown) on a surface of the circuit board 102 with solder, and thereby the header 20 is mounted on the surface of the circuit board 102 .

The socket 10 and the header 20 constituting the connector assembly 1 can be produced by the manufacturing method disclosed in Japanese Patent Application Publication No. 2012-059420, and accordingly the method for the connector assembly 1 is not described in detail herein.

In the embodiment, the connector assembly 1 includes the socket 10 (female connector) and the header 20 (male connector). The socket 10 includes the film substrate 11 and the pads 12 ( 12 A, 12 B). The film substrate 11 is made from insulating material to be shaped like a thin board with flexibility, and includes through holes 14 (the connection through holes 14 A and the combining through holes 14 B) pierced in the film substrate 11 in the thickness direction (the first direction). Each pad 12 is formed around a corresponding through hole 14 on a surface (the second surface) of the film substrate 11 . The header 20 includes conductive protrusions (the posts 22 formed of the connection posts 22 A and the combining posts 22 B) each of which is adapted to be inserted into a corresponding through hole 14 to be electrically connected to the pad 12 around the hole 14 . The film substrate 11 includes the slots 15 ( 15 A, 15 B) each of which is formed to extend along a plane of the film substrate 11 with one end side (a first end side) thereof ( 15 ) connected to a corresponding through hole 14 . The part 17 (pad-free part 17 A, 17 B) is placed at least part of a region, on the surface of the film substrate 11 , which is present at other end side of the slot 15 and free to be bent by the post 22 .

Thus, each part 17 without pad 12 is placed at a region which is present at the second end sides of a corresponding slots 15 and free to be bent by a corresponding post 22 (i.e., spring piece 18 A, 18 B). A part 17 without pad 12 in each spring piece 18 A, 18 B consists of only the film substrate 11 and is easy to bend in comparison with part with pad 12 therein. It is therefore possible to reduce stress occurring in each spring part (i.e., spring piece 18 A, 18 B) for electrical connection and fit holding, because a stress occurring when each post 22 is inserted into a corresponding through hole 14 is reduced by the peripheral part of the through hole 14 being bent by the post 22 .

Each post 22 of the header 20 includes a head 24 at a tip side thereof, and the head 24 has a cross section larger than that of a base side of the post 22 . Each pad 12 is adapted to climb over the head 24 of a corresponding combining post 22 to come into contact with the base side (the neck 23 ) of the post 22 .

Thus, each pad 12 is in contact with the base side (the neck 23 ) of a corresponding combining post 22 , and accordingly each pad 12 hooks to the head 24 of the post 22 , thereby preventing the post 22 from coming out of a corresponding through hole 14 . In the embodiment, only each combining post 22 B is shaped like a mushroom, but each connection post 22 A may be shaped like a mushroom in the same way as each combining post 22 B.

The header 20 includes the combining posts (combining protrusion) 22 B each of which is adapted to be inserted into a corresponding combining through hole 14 B provided in the film substrate 11 to be mechanically combined with the combining through hole 14 B.

Thus, each combining post (combining protrusion) 22 B is combined with a corresponding combining through hole 14 B, thereby preventing the socket 10 from coming out of the header 20 to mechanically and rigidly combine the socket 10 with the header 20 .

Although the present invention has been described with reference to certain preferred embodiments, numerous modifications and variations can be made by those skilled in the art without departing from the true spirit and scope of this invention, namely claims.