WO2007140075A1

WO2007140075A1 - Connector and connector system

Info

Publication number: WO2007140075A1
Application number: PCT/US2007/068058
Authority: WO
Inventors: Hiroyuki Matsuoka
Original assignee: 3M Innovative Properties Co
Current assignee: 3M Innovative Properties Co
Priority date: 2006-05-26
Filing date: 2007-05-02
Publication date: 2007-12-06
Anticipated expiration: 2008-11-26
Also published as: TW200814440A; JP2007317554A

Abstract

A connector includes an electrical insulating body, a terminal element that is supported on the body and is connected to a core conductor W of a cable C, and a grounding structure that is provided on the body so as to be insulated from the terminal element and is connected to a shield layer of the cable C. The grounding structure includes a grounding member fixed to the body. The grounding member is disposed along a surface proximate to the body of the shield layer of the cable C having the core conductor W connected to the terminal element and is connected to the shield layer. The grounding member includes a cable-connecting section connected to the shield layer of the cable C, and a ground-contacting section capable of being brought into conductive contact with a corresponding grounding element of a counterpart connector.

Description

CONNECTOR AND CONNECTOR SYSTEM

FIELD OF THE INVENTION

The present invention relates to a connector connected to a cable. The present invention also relates to a connector mounted on a circuit board. The present invention further relates to a connector system for connection of a circuit board.

BACKGROUND

A connector for connecting to a cable comprising an electrical insulating body, a terminal element that is supported on the body and is connected to a core conductor of a cable and a grounding structure that is provided on the body so as to be insulated from the terminal element and is connected to a shield layer of the cable, has been conventionally known. Such a cable connector can be appropriately applied to a coaxial cable having, for example, a braid or foil outer conductor (a shield layer) along the entire length of the cable outside the insulator surrounding a core conductor (signal wire). A coaxial cable is widely used in various electrical and electronic equipments including communication apparatuses, information apparatuses, medical apparatuses, measuring instruments, and the like, because it is unlikely to be affected by external noise. In this case, the outer conductor of the coaxial cable is electrically connected via a grounding structure of the cable connector to the ground potential (for example, a grounding section of a circuit board) of an apparatus. In recent years, high density connection of signal wires in a small size electronic apparatus such as a mobile telephone has been increasingly required, and in order to meet this requirement, a plurality of highly flexible coaxial cables having minimum size core conductors are used in flat shape. A connector system having terminal elements arranged in extremely narrow pitch has been developed to connect an assembly of such flat coaxial cables to a circuit board. In a connector system of this type, because of constraint concerning space for mounting parts and workability in a small electronic device, miniaturization has been pursued for effective reduction of mounting area and mounting height on a circuit board. For example, Japanese Unexamined Patent Publication (Kokai) No. 2005-302417 discloses a small height connector system for cable-board connection capable of meeting the requirement of high density connection of signal wires.

The connector system disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2005-302417 includes a plug connector connected to a plurality of coaxial cables and a receptacle connector surface-mounted to a printed circuit board. The plug connector includes a plurality of male contacts supported on a housing body and a metal shell fixed to upper portion of the housing body. A common ground bar is attached to the outer conductor of the plurality of coaxial cables, the ground bar being in contact with the inner surface of the shell. On the other hand, the receptacle connector includes a plurality of female contacts and a metal shell mounted to the housing body and fixed to the circuit board. When the plug connector connected to the coaxial cables is fit onto the receptacle connector mounted on the circuit board, the shell on the plug side is brought into contact with the shell on the receptacle side, whereby the outer conductor of individual coaxial cables is grounded to the circuit board.

SUMMARY

In the above described connector system as disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2005-302417, the ground bar attached to the outer conductor of a plurality of coaxial cables is brought into contact with the inner surface of the shell fixed to the upper portion of the housing body of the plug connector, so that individual coaxial cables are grounded to the circuit board via both connectors. In such a construction, the shell of the plug connector is fixed to the housing body in such a manner that it covers the plurality of coaxial cables from above. Therefore, wide space is necessarily provided between the shell and the housing body in order to accommodate the coaxial cables. Thus, at the time of fitting the connector, or in the state of connector mounted to the circuit board after fitting, when an external force is applied to the housing body of the plug connector, the force may relatively easily give rise to flexure or warp of the shell. This may produce unstable positional relationship between the shell and the coaxial cable in the plug connector, and as a consequence, stability and reliability of the grounding of the coaxial cable may be degraded.

Reduction of mounting area and mounting height on the circuit board is seriously required, especially in a connector system for connecting cable to a circuit board in a small size electronic device, as described above. However, when outer dimensions of a connector system are reduced to meet this requirement, it is sometimes difficult to disconnect and separate the connector for cables from the connector for the circuit board once they were fitted to each other. For example, when an operator wishes to pick up a connector for cable with fingers or a tool and separate it from a connector for circuit board, it may be sometimes difficult to find sufficient space for inserting the fingers or the tool, or the connectors may be damaged by the hard and difficult operation. On the other hand, it is desired that, in a connector system of this type, a connector for the cable and a connector for the circuit board have complementary fitting structure such that corresponding terminal elements of both connectors can be stably held in proper contact with each other. When a connector system with reduced outer dimensions has such a complementary fitting structure, it tends to be more difficult to separate the connector for cable safely from the connector for circuit board.

It is an object of at least one embodiment of the present invention to provide a connector for connection to a cable, comprising a grounding structure to be connected to a shield layer of the cable, which is capable of improving the stability and reliability of the cable grounding structure in the grounding structure. It is another object of at least one embodiment the present invention to provide a connector to be mounted to a circuit board, which is capable of stably maintaining proper contact of terminal elements with the terminal elements of the counterpart connector and which permits separation work of the counterpart connector to be carried out safely and easily. It is still another object of at least one embodiment the present invention to provide a connector system for connecting a cable to a circuit board, which is capable of improving stability and reliability of the cable grounding structure.

It is still another object of at least one embodiment the present invention to provide a connector system for connecting a cable to a circuit board, which is capable of maintaining proper contact of terminal elements of mutually fitted connectors with each other even when outer dimension is reduced, and which permits separation work of connectors from each other to be carried out safely and easily.

One embodiment of the invention provides a connector comprising an electrical insulating body, a terminal element supported on the body and adapted to be connected to a core conductor of a cable, and a grounding structure provided on the body while being insulated from the terminal element and adapted to be connected to a shield layer of the cable, characterized in that the grounding structure comprises a grounding member fixed to the body; and that the grounding member is disposed along a surface, at a side proximate to the body, of the shield layer of the cable with the core conductor of the cable being connected to the terminal element, and is connected to the shield layer.

In accordance with one embodiment of the invention, the shield layer of a cable is connected to the grounding member fixed to the body at a position that is closer to the body than itself, and ground potential is thereby imparted to the shield layer of the cable. In this construction, the grounding member can be directly and securely fixed to the body, since there is no space formed between the body and the grounding member for receiving the cable. Therefore, even when an external force is applied to the body during connector fitting work or in the state of the connector mounted to the circuit board after fitting, the body reinforcing function of the grounding member exhibits synergistic effect so as to reliably prevent flexure or warp from being produced. As a result, relative position of the grounding member with respect to the cable in the connector is stabilized, and stability and reliability of the cable grounding function is thereby significantly improved. Since the grounding member can be soldered to the surface of the shield layer of the cable proximate to the body, so that solder protrusion outside the body may be substantially eliminated. Such a construction is very advantageous in reducing outer dimension (especially in height direction) of the connector over the previous construction in which a metal shell disposed along the outer surface of the connector is soldered to the shield layer of the cable, and as a result, a further height reduction of connector system including the connector can be achieved without degrading stability and reliability of the above-described cable grounding function.

In accordance with a second embodiment of the invention, the grounding member itself has the ground-contacting section extended from the cable-connecting section, so that, without requiring a conductive element as a separate member, the shield layer of the cable can be stably grounded to the corresponding grounding element of the counterpart connector. Such a construction contributes to the reduction of the number of parts of a connector and to the simplification of the assembling work.

In accordance with a third embodiment of the invention, in a coaxial cable assembly consisting of an array of a plurality of highly flexible coaxial cables having minimum size core conductors, the grounding member can be stably grounded in good electrical conduction to the shield layers of all the coaxial cables via the grounding plate. Thus, stability and reliability of the grounding function for a flat and multi-core coaxial cable assembly can be further improved.

In accordance with a fourth embodiment of the invention, the cable-connecting section of the grounding member has the same rectangular plate shape as the grounding plate so that contact resistance between the cable-connecting section and the grounding plate can be decreased. Further, since the grounding member has the ground-contacting section on both longitudinal ends of the cable-connecting section, the connection of the grounding member to the grounding element of the counterpart connector can be improved. In accordance with a fifth embodiment of the invention, body reinforcing function of the grounding member and deformation preventing function of the grounding member and the body are further improved, and workability of the connector assembling is also improved.

In accordance with a sixth embodiment of the invention, apart from the grounding member, a shield member is provided at a position so as to cover the shield layer of the cable, so that the shield layer may be connected to the grounding member. Thus, by connecting the shield member to the ground potential, shield structure for the signal transmission path in the connector can be established, and high speed transmission characteristics of the connector system including the connector can be thereby improved. In accordance with a seventh embodiment of the invention, the counterpart connector can be stably fitted to the connector mounted on the circuit board so as to be received in its receptive recess, and in addition, an operator can smoothly insert his fingers or tools into a plurality of notches provided in the surrounding wall of the body so as to carry out the picking operation and pulling-out operation to the counterpart connector, to thereby separate the counterpart connector from the connector on the circuit board. Thus, even when outer dimension of the connector is reduced, proper mutual contact to the terminal elements of the counterpart connector can be stably maintained and separation operation of the counterpart connector can be safely and easily carried out.

In accordance with an eighth embodiment of the invention, an article-catching type tool such as a pair of tweezers can be used to exert a stable separating force by catching to the counterpart connector to separate it from the connector, and damage to both connectors can be thereby more effectively prevented. In accordance with a ninth embodiment of the invention, the grounding element of the shield member is brought into conductive contact with the counterpart connector, and a common ground potential is thereby imparted both to the connector and to the counterpart connector so that high level shield structure for the signal transmission path in both connectors can be established, and high speed transmission characteristics of the connector system is thereby improved.

In accordance with a tenth embodiment of the invention, in a connector system for cable-circuit board connection, stability and reliability of the cable grounding function can be improved. Even when outer dimension of the connector is reduced, proper mutual contact to the terminal elements of the counterpart connector can be stably maintained and separation operation of the connectors from each other can be safely and easily carried out.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 A perspective view showing a connector in assembled state according to an embodiment of the present invention; (a) a view as seen from the shield member side, and (b) a view as seen from the side of the terminal element contact section.

Fig. 2 An exploded perspective view showing the connector of Fig. 1. Fig. 3 A perspective view showing the connector of Fig. 1; (a) a terminal element, and (b) a ground-contacting section.

Fig. 4 A perspective view showing the connector of Fig. 1 in semi-assembled state. Fig. 5 A sectional view showing the connector of Fig. 1 taken along the line V-V.

Fig. 6 A perspective view showing a connector in assembled state according to another embodiment of the present invention.

Fig. 7 An exploded perspective view showing the connector of Fig. 6. Fig. 8 A perspective view showing a connector system in assembled state according to an embodiment of the present invention.

Fig. 9 A sectional view showing the connector system of Fig. 8 taken along the line IX-IX. Fig. 10 A plan view showing the connector system of Fig. 8.

Fig. 11 A perspective view showing a modification of the connector of Fig. 1; (a) a view as seen from the shield member side, and (b) a view as seen from the side of the terminal element contact section.

Fig. 12 A partial view showing the modification of Fig. 11; (a) an enlarged plan view, and (b) a sectional view taken along the line XII-XII.

DETAILED DESCRIPTION

Now, the present invention will be described in detail below with reference to appended drawings showing embodiments thereof. Throughout the drawings, corresponding constituents are denoted by common reference numerals.

Fig. 1 is a perspective view showing a connector 10 according to an embodiment of the present invention in an assembled state. Fig. 2 is an exploded perspective view showing the connector 19. Fig. 3 is a perspective view showing main constituents of the connector 10. Fig. 4 is a perspective view showing semi-assembled state of the connector 10. Fig. 5 is a sectional view showing an essential part of the connector 10. A connector

10 is a cable connector having terminal elements to be connected to core conductors of cables, and, as will be described later, can be advantageously applied to a connector system for connecting a cable assembly in which a plurality of highly flexible coaxial cables having minimum size core conductors are arranged in a flat shape to a circuit board. In this case, the other connector to which the connector 10 is to be connected (herein referred to as "counterpart connector") is constructed as a substrate-connector mounted to a circuit board. However, the connector according to the present invention is not limited to such an application, but may be implemented as various connectors applied to other connector applications. Also, the present invention is not limited to a particular number of incorporated terminal elements, but may equally be applied to a connector having a single terminal element.

The connector 10 includes an electrical insulating body 12, a plurality of terminal elements 14 supported on the body 12, and a grounding structure 16 provided on the body 12 so as to be insulated from the terminal elements 14 (Fig. 1). The body 12 is a thin plate member of generally rectangular shape in plan view integrally molded from an electrically insulating resin material, for example, by injection molding process, and includes a first support section (terminal element support section) 18 for supporting a plurality of terminal elements 14 in spaced-apart parallel arrangement, and a second support section 20 along the other long edge and a pair of short edges extending in transversal direction on which a grounding structure 16 is provided (Fig. 1).

On one major surface 12a of the body 12, a plurality of core conductor holding grooves 22 for individually receiving a plurality of cable core conductors W to be connected to a plurality of terminal elements 14, are formed in parallel arrangement at equal spacing in the longitudinal direction of the body (Fig. 2, Fig. 5). On the other major surface 12b (on the side opposite to the major surface 12a) of the body 12, at generally center position in the transversal direction, a concavity 24 for bringing a plurality of terminal elements 14 into contact with the corresponding terminal elements of the counterpart connector (to be described later) is formed adjacent to the first support section 18 (Fig. l(b), Fig. 5).

All of the plurality of terminal elements 14 have the same shape and dimensions, and integrally fixed to the first support section 18, for example, by an insert molding process, and are aligned and supported in parallel to each other at a predetermined equal spacing. Each terminal element 14 is formed in generally C-shape from a metal plate of good electrical conductivity, for example, by press shaping process, and integrally includes a core conductor connection section 26 to be connected to a core conductor W of a cable C, and a contact section 28 to be brought into conductive contact with the corresponding terminal element of the counterpart connector (Fig. 3(a)). Each terminal element 14 is fixedly supported on the first support section 18 with the core conductor connection section 26 exposed on the side of major surface 12a of the body 12 and with the contact section 28 exposed on the side of major surface 12b of the body 12 (Fig. 5). In the embodiment shown, the contact section 28 of each terminal element 14 exposed on the side of major surface 12b of the body 12, is formed as a male contact section protruding with a pair of contact portions 28a. As will be described later, when the connector 10 is connected in fitting to the counterpart connector, the male contact section 28 of individual terminal elements 14 is brought in complementary fitting into conductive contact with a female contact section of the corresponding terminal element of the counterpart connector. In place of the construction shown in which a plurality of terminal elements 14 are formed in insert molding on the first support section 18 of the body 12, it is also possible to employ the construction in which the terminal element of a suitable form is assembled to the first support section that has been preformed in a suitable shape. The grounding structure 16 includes a grounding member 30 fixed to and supported on the second support section 20 of the body 12 (Fig. l(b), Fig. 2). The grounding member 30 is fixedly disposed along the surface Ga of the shield layer G of the cable C having the core conductor W connected to the terminal element 14 on the side proximate to the body 12, and is connected to the shield layer G (Fig. 5). Thus, the grounding member 30 is disposed, as seen from the body 12, at a position closer than the shield layer G of the cable C, and is directly fixed to the body 12 without forming space for receiving the cable C therebetween. The grounding member 30 is a frame-like member formed from a metal plate of good electrical conductivity by, for example, press shaping process in generally U-shape in plan view, and includes integrally a cable- connecting section 32 in the shape of thin rectangular plate to be connected to the shield layer G of the cable C, and a ground-contacting section 34 extended from the cable- connecting section 32 and capable of being brought into conductive contact with the corresponding grounding element (to be described later) of the counterpart connector (Fig. 3(b)).

Here, a cable C to which the connector 10 according to the embodiment shown can be applied is a highly flexible coaxial cable C having a core conductor W of minimum diameter with a braid or foil shield layer (outer conductor) G over the entire periphery outside an insulator D surrounding the core conductor W, whole shield layer G covered by an outer resin sheath S (Fig. 5). The connector 10 is connected to a coaxial cable assembly CA formed by arranging a plurality of such fine coaxial cables C in a row and by processing only the tip portion in a flat shape (Fig. 1). The coaxial cable assembly CA are subjected to processing such that the outer sheath S, the shield layer G, and the insulator D are removed step by step over a required length of the end portion of each of the plurality of coaxial cables C so as to expose the core conductor W (Fig. 5). A pair of grounding plates P made of thin metal plate of good electrical conductivity are provided such that the grounding plates P are disposed so as to sandwich, from above and below, the exposed shield layers G of the plurality of parallel coaxial cables C, and uniformly fixed to all the shield layers G, for example, by soldering. A coaxial cable assembly CA having been subjected to such an end-tip processing is in general commercially available from cable manufacturers. Or, the grounding plate P can be provided as a constituent of the connector 10. A grounding member 30 is fixedly connected, for example by soldering or welding, to one (closer to the body 12) of the grounding plates P commonly connected to the individual shield layers G of the plurality of coaxial cables C (Fig. 5). More specifically, the grounding member 30 has a cable-connecting section 32 having the same rectangular shape as the grounding plate P disposed so as to be superposed over substantially whole of the one grounding plate P closer to the body 12, and is connected in good electrical conduction to the grounding plate P over the entire superposition surface 32a of the cable-connecting section 32 or at desired points thereof. When the grounding member 30 is fixed to the grounding plate P by welding, through-holes are formed at desired positions of the grounding member 30, and electrical welding or laser welding may be performed using these through-holes with the grounding member 30 placed in superposition upon the grounding plate P. In order to carry out welding with the grounding member 30 incorporated into the body 12, similar through-holes may be formed at desired positions on the body 12.

In the grounding member, the ground-contacting section 34 is provided on each of both longitudinal ends of the cable-connecting section 32. Each ground-contacting section includes a pair of first contact pieces 34a opposed to each other and extending generally parallel to the extending direction of the cable-connecting section 32 and a second contact piece 34b disposed between the first contact pieces 34a, and a contact point 36 is formed on each outer surface of the contact pieces 34a, 34b for conductively making contact with the grounding elements (to be described later) of the counterpart connector (Fig. 3(b)). Depending upon the application of the connector 10, varied number of ground-contacting sections 34 can be provided on various other positions than those described above.

The grounding member 30 is integrally fixed to and supported on the second support section 20 of the body 12, for example by insert molding process. Here, on the second support section 20 of the body 12, adjacent to the plurality of core conductor holding grooves 22, an opening 38 of generally rectangular shape in plan view extending in longitudinal direction of the body is penetratingly formed between the major surface

12a and the major surface 12b (Fig. 5). Fitting sections 40 for fitting to the electrical insulating body of the counterpart connector (to be described later) are formed at both longitudinal ends of the body 12 (Fig. 2).

The grounding member 30 is disposed, in a state properly fixed to the body 12, with the cable-connecting section 32 having most of both surfaces 32a, 32b exposed to the entire opening 38 of the second support section 20 and with a pair of ground contact section 34 each having all the contact points 36 and the end region 34c of the second contact piece 34b exposed to the corresponding fitting section 40 (Fig. 1, Fig. 2). Also in this state, a concavity 42 is formed adjacent to the plurality of core conductor holding grooves 22 on the major surface 12a of the body 12 for accommodating the whole portion of the coaxial cable assembly CA having been subjected to the end processing with a pair of grounding plates P attached thereto (Fig. 4, Fig. 5). Besides the illustrated construction in which the grounding member 30 is insert-molded to the second support section 20, various attaching methods can be employed, for example using a construction in which a grounding member of suitable shape is incorporated into the second support section having been preformed in appropriate shape, as long as the grounding member 30 can be securely fixed to the body 12.

As will be described later, when the connector 10 is fitted and connected to the counterpart connector, individual ground-contacting sections 34 of the grounding member 30 are brought into conductive contact with the corresponding grounding elements (to be described later) of the counterpart connector. The shield layers G of the plurality of coaxial cables C connected via the grounding plate P to the grounding member 30 of the connector 10, are thereby electrically connected to the ground potential of the counterpart connector (for example, grounding section of the circuit board to which the counterpart connector is mounted).

The connector 10 further includes a shield member 44 attached to the body 12 so as to be insulated from the plurality of terminal elements 14. The shield member 44 is a flat plate-like member formed from a metal plate of good electrical conductivity into a generally rectangular shape in plan view by, for example, press molding process, and integrally includes a main portion 44a for shielding substantially the entire major surface 12a of the body 12, a pair of attaching portion 44b extending from both longitudinal ends of the main portion 44a and fitted to the body 12, and an abutting portion 44c between these attaching portion 44b (Fig. 2).

On each fitting section 40 of the body 12, a pair of attaching grooves 40a are formed around the exposed end region 34c of the second contact piece 34b of each contact section 34 of the grounding member 30. The shield member 44 is attached to the body 12 by having the individual attaching portion 44b bent in L-shape fitted into the corresponding fitting groove 40a of the fitting section 40 (Fig. l(a)). The shield member 44 in a state properly attached to the body 12 by the attaching portion 44b, is disposed, slightly separated from the plurality of terminal elements and the core conductors W of the plurality of cables C connected to the terminal elements 14, on the side opposite to the grounding member 30 with respect to the shield layers G of the cables C, and electromagnetically shields all the terminal elements 14 and the cables C disposed on the major surface 12a of the body (Fig. 5).

In a state properly attached to the body 12, the shield member 44 has individual abutting portion 44c abutted in good electrical conduction to the exposed end regions 34c of the second contact piece 34b of each ground-contacting section 34 of the grounding member 30 exposed on the fitting section 40, and is thereby electrically connected to the grounding member 30 (Fig. 1, Fig. 2). As will be described later, by fitting and connecting the connector 10 to the counterpart connector, the ground potential is imparted to the shield member 44 via the grounding member 30 and the corresponding grounding element of the counterpart connector.

In the connector 10 having above construction, the shield layers G of a plurality of cables C are connected via the grounding plate P to the grounding member 30 that is fixed to the body 12 at a position closer to the body 12 than itself, and the ground potential of the grounding member 30 can be thereby imparted to the shield layer G of individual cable C. In this construction, unlike the construction as described in Japanese Unexamined Patent Publication (Kokai) No. 2005-302417, no space is formed between the body 12 and the grounding member 30 for receiving the cable C, so that the grounding member 30 is directly and securely fixed to the body 12. Therefore, when an external force is applied to the body 12 during the connector fitting work or in the state of being mounted to the circuit board after fitting, the body reinforcing function of the grounding member 30 exhibits synergistic effect so as to reliably prevent flexure or warp from being produced in the grounding member 30 (and the body 12). As a result, relative positional relationship of the grounding member 30 and the cables C in the connector 10 becomes more stable, and stability and reliability of the cable grounding function can be significantly improved.

Further, in the connector 10, the grounding member 30 can be soldered to the surface Ga proximate to the body 12 of the shield layers G of the plurality of cables C, so that the solder protrusion outside the body 12 can be eliminated. Compared to the construction in which a metal shell disposed along the outer surface of the connector is soldered to the shield layer of the cable, the construction of the present invention is very advantageous in reducing outer dimensions (especially in height direction) of the connector 10, and as a result, further height reduction of a connector system including the connector 10 can be achieved without impairing stability and reliability of the above described cable grounding function. In the connector 10 according to the embodiment shown, the grounding member 30 itself has the ground-contacting section 34 extended from the cable-connecting section 32, so that the shield layers G of the plurality of cables C can be stably grounded to the grounding element of the counterpart connector without need to provide a conductive element as a separate member. This construction contributes to reduction of the number of parts for the connector 10 as well as simplification of assembling process.

Also, the connector 10 of the embodiment shown is constructed such that, for a coaxial cable assembly CA consisting of an array of a plurality of highly flexible coaxial cables C having core conductors W of minimum diameter, a grounding member 30 is stably connected via a grounding plate P in good electrical conduction to the shield layers G of all the coaxial cables C. Thus, stability and reliability of the grounding function to the coaxial cable assembly CA having multiple core conductors in flat form can be further improved

In particular, the cable-connecting section 32 of the grounding member 30 has the same rectangular-plate shape as the grounding plate P, so that the contact resistance between the cable-connecting section 32 and the grounding plate P can be reduced. Also, the grounding member 30 has the ground-contacting section 34 on both longitudinal ends of the cable-connecting section 32, so that the connection of the grounding member 30 to the grounding element of the counterpart connector can be further stabilized.

With the construction in which the grounding member 30 is integrally fixed to the body 12 in one unit by insert molding, the body reinforcing function of the grounding member 30 and the deformation preventing function to prevent deformation of the grounding member 30 and the body 12 can be further improved, and in addition, workability of the assembling of the connector 10 can be improved. Also, since, apart from the grounding member 30, the shield member 44 is provided at a position so as to cover the exposed portion of the cable C and the shield member 44 is connected to the grounding member 30, the shield member 44 can be connected to the ground potential to thereby establish the shield structure for the signal transmission path in the connector 10, and to improve the high speed transmission characteristics of the connector system including the connector 10.

The connector 10 having above construction can accommodate a high density connection structure aimed at size reduction of the core conductor W of the cable C and pitch narrowing of the array of terminal elements 14 by employing the cable connection structure having excellent stability and reliability. In the high density connection structure that can be realized with the connector 10, for example, outer diameter of the cable core conductor is 0.09 mm or less (AWG (American Wire Gauge) 40 or higher), pitch of the arrangement of the terminal elements 14 is 0.3 mm or less. In addition, dimension of the connector 10 in height direction can be reduced to about 1 mm.

Figs. 6 and 7 are views showing a connector 50 according to another embodiment of the present invention in an assembled state and in an exploded view, respectively. The connector 50 is a connector for circuit board having terminal elements connected to conductors of a circuit board, and is constructed as the counterpart connector of the above- described cable connector 10. However, the connector according to the present invention is not limited to such an application, but may be implemented as various connectors adapted to other connection applications. Also, the present invention is not limited to a particular number of incorporated terminal elements, but may also be applicable to a connector having a single terminal element. The connector 50 includes an electrical insulating body 52, a plurality of terminal elements 54 supported on the body 52, and a shield member 56 attached to the body 52 so as to be insulated from the terminal elements 54. The body 52 is a thin plate-like member of generally rectangular shape in plan view integrally formed from an electrically insulating resin material by, for example, injection molding, having a first support section (that is, terminal element support section) 58 along one long edge extending in the longitudinal direction for supporting the plurality of terminal elements 54 in spaced apart parallel arrangement, and a second support section 60 along a pair of short edges extending in the transversal direction for supporting the shield member 56. A plurality of terminal element holding grooves 62 are formed in the first support section 58 in parallel arrangement at equal spacing in the longitudinal direction of the body for individually receiving a plurality of terminal elements 54.

On the major surface 52a of the body 52, along the long edge on the side opposite to the first support section 58, there is provided a edge wall section 54 projecting to a height smaller than the first support section 58. In the region surrounded by the first support section 58, a pair of the second support section 60 and the edge wall section 64, a receptive recess 66 is formed for detachably receiving the counterpart connector (that is, the connector 10). In addition, each of the second support section 60 of the body 52 defines a fitting concavity 68 for complementarily receiving the fitting section 40 (Fig. 1) of the body 12 of the counterpart connector 10 as a part of the receiving concavity 66. In this construction, a pair of second support section 60 and the edge wall section 64 functions as a surrounding wall section of generally C-shape in plan view to define, in cooperation with the first support section 58, the receptive recess 66. This surrounding wall section (the second support section 60 and the edge wall section 64), coupled with the first support section 58, acts to come into contact with the outer circumference surface of the body 12 of the counterpart connector 10 and to guide and hold the counterpart connector 10 into proper position in the receptive recess 66. Thereby, improper fitting (for example, slant fitting) of the counterpart connector 10 relative to the connector 50 can be reliably prevented even when outer dimension is reduced as far as possible.

A plurality of terminal elements 54 are constructed to include two types of terminal element group 54A, 54B having generally the same shape and partially different longitudinal dimensions. Each of the terminal elements 54A, 54B is a pin-like member formed into specified shape from a metal plate of good electrical conductivity by, for example, press molding process, and integrally includes an intermediate attachment section 70 press-fitted into the terminal element holding groove 62 of the first support section 58 of the body 52, a contact section 72 extended from the attachment section 70 to be exposed on the surface of the first support section 58 and the receptive recess 66 as one end, and a lead section 74 extended from the attachment section 70 in the direction opposite to the contact section 72 to project outside of the body 52 as the other end. The two types of terminal elements 54A, 54B have same dimensions and shape except that the length of respective lead sections 74 to be connected to the conductor of the circuit board (to be described later) is different. The contact section 72 of each terminal element 54 is formed as a female contact section bent in generally U-shape having a pair of contact portions 72a. As will be described later, when the connector 50 is fitted and connected to the counterpart connector 10, the female contact section 28 (Fig. 5) of the corresponding terminal element 14 of the counterpart connector 10 is complementarily fitted into the female contact section 72 of the individual terminal element 54 and is brought into conductive contact with it. The two types of terminal elements 54 A, 54B are arranged alternatingly in the longitudinal direction of the body 52, and the lead sections 74 of the terminal elements 54A, 54B are arranged in staggered projection along the one long edge of the body 52. Such a staggered arrangement of the terminal element lead section 74 enables narrow pitch arrangement of the terminal elements 54 in correspondence to the aforementioned high density connection structure of the connector 10 to be achieved while preventing short-circuit of the conductor pattern on the circuit board. In place of above construction in which a plurality of terminal elements 54 are press-fitted into the first support section 58 of the body 52, it is also possible to employ the construction in which a plurality of terminal elements 54 are integrally incorporated as an insert at the time of molding of the body 52.

The shield member 56 is a frame-like member formed from a metal plate of good electrical conductivity in generally U-shape in plan view by, for example, press molding process, and integrally includes a terminal element shielding section 76 for shielding entire attachment section 70 of the plurality of terminal elements 54 attached to the first support section 58 of the body, and a grounding element 78 extended from the terminal element shielding section 76 and capable of being brought into conductive contact with the ground- contacting section 34 of the grounding member 30 of the counterpart connector 10 (Fig. 1). In the embodiment shown, the grounding element 78 is provided on each of both longitudinal ends of the terminal element shielding section 76 in the shape of rectangular plate. Each grounding element 78 has a pair of first contact pieces 78a extending generally in parallel to the direction of extension of the terminal element shielding section 76 and opposed to each other, a second contact piece 78b disposed between the pair of first contact pieces 78a and a grounding piece 78c projecting outward on the side opposite to the second contact piece 78b. On each of the outer surfaces of the first and the second contact pieces 78a, 78b, a contact point 80 to be brought into conductive contact with each of the contact points 36 (Fig. 3(b)) provided on each ground-contacting section 34 of the grounding member 30 of the counterpart connector 10, is formed.

The shielding member 56 is fixedly supported on and assembled to the body 52 such that both grounding elements 78 cover the corresponding second support section 60 of the body 52. In this state, the first and the second contact pieces 78a, 78b of the grounding elements 78 are disposed inside the fitting concavity 68 of the second support section 60 of the body and the grounding piece 78c of the grounding element 78 is disposed so as to project outward from the second support section 60 of the body. The shielding member 56 is disposed, in the state of being properly assembled to the body 52 via the grounding element 78, with the terminal element shielding section 76 slightly spaced apart from the exposed surface of the attachment section 70 of the plurality of terminal elements 54 supported on the first support section 58 of the body, so as to electromagnetically shield the terminal elements 54. As will be described later, when the connector 50 is fitted and connected to the counterpart connector 10, individual grounding element 78 of the shield member 56 is brought into conductive contact with the corresponding ground-contacting section 34 of the grounding member 30 of the counterpart connector 10, whereby the ground potential of the connector 50 (for example, the ground potential that is imparted to the connector 50 via the grounding piece 78c of the grounding element 78 from the circuit board to which the connector 50 is mounted) is connected to the shield layer G (Fig. 5) of the plurality of the coaxial cable C that is connected via the grounding plate P to the grounding member 30 of the counterpart connector 10. As a result, high level shield structure is established for the signal transmission path in the connector system consisting of the cable connector 10 and the connector 50 for the circuit board, and high speed transmission characteristics of the connector system is improved.

Figs. 8 to 10 are views showing a connector system 90 composed of the cable connector 10 and the connector 50 for the circuit board combined detachably with each other. In the connector system 90, when the cable connector 10 and the connector 50 for circuit board are connected to each other, the connector 10 as a whole is received complementarily in the receptive recess 66 provided in the body 52 of the connector 50, and the fitting sections 40 provided on both longitudinal ends of the connector body 12 are complementarily fitted into corresponding fitting concavity 68 provided on both longitudinal ends of the connector body 52 such that both connectors 10, 50 are held in proper fitting state.

In this proper fitting state, the corresponding terminal elements 14, 54 of the two connectors 10, 50, are connected to each other stably by two-point contact of the respective contact sections 28, 72 that are in male-female relationship with each other (Fig. 9). Moreover, in the proper fitting state, the grounding member 30 incorporated into the body 12 of the connector 10 has the ground-contacting section 34 on both longitudinal ends thereof respectively connected to corresponding grounding elements 78 of the shield member 56 assembled to the connector 50 stably by three point contact (contact points 36, 80).

Here, the connector 50 surface mounted to the circuit board R has individual terminal elements 54 connected by the lead section 74 to corresponding signal conductor Sl on the circuit board R by means of soldering, etc., and both grounding elements 78 of the shield member 56 connected by the grounding piece 78c to corresponding grounding conductors S2 on the circuit board R by means of soldering, etc. (Fig. 9). As a result, the ground potential is imparted to the shield member 44, 56of both connectors 10, 50, and to the shield layer G of the plurality of cables C connected to the connector 10, and stability and reliability of cable grounding function in the connector system 90 for connecting cable -circuit board can thereby be improved.

In the connector system 90 described above, when two connectors 10, 50 are in proper fitting state, the connector 50 for circuit board is composed such that mainly the bottom plate 66a of the receptive recess 66 of the body 52 and the female contact section 72 of each terminal element 54 are superposed in the height direction of the cable connector 10 (Fig. 9). With such construction in which superposition in height direction is reduced as far as possible, the connector system 90 can improve overall height reduction corresponding to structural characteristics of the cable connector 10 capable of reducing outer dimensions (especially in height direction).

As has been mentioned above, when height is reduced in a conventional connector system, it may sometimes become difficult to separate the mutually fitted cable connector and the connector for circuit board from each other. In order to resolve such inconvenience, the connector 50 for circuit board has a plurality of notches 82 with openings in communication with the receptive recess 66 of the body 52 provided dispersedly in the surrounding wall section (that is, the second support section 60 and the edge wall section 64) (Fig. 6, Fig. 7).

As shown in Fig. 10, in mutually fitting connectors 10, 50, when an operator wishes to pick up the cable connector 10 with fingers or tools (not shown) and separate it from the connector 50 for circuit board, the plurality of notches 82 provided on the surrounding wall section 60, 64 of the body 52 acts very effectively as space for fingers or tools to be inserted smoothly. Therefore, in the connector system 90 having reduced outer dimensions, notwithstanding the fact that, as described above, complementary fitting structures (fitting section 40, surrounding wall section 60, 64, receptive recess 66, etc.) are provided capable of holding corresponding terminal elements 14, 54 of two connectors 10, 50, and the grounding member 30 and the shielding member 56, respectively, in proper contact state, damage of the connectors 10, 50 due to difficult work is not produced and the cable connector 10 can be safely separated from the connector for circuit board. Thus, the connector 50 mounted to the circuit board R permits, even when the outer dimensions are reduced, proper contact state of the terminal element 14 of the counterpart connector 10 and the terminal element 54 to be stably maintained, and the separation work for separating the counterpart connector 10 to be safely and easily carried out. Similarly, the connector system 90 for connecting cable to circuit board permits, even when the outer dimensions are reduced, proper contact state of the terminal elements 14, 15 of the mutually fitting connectors 10, 50 to be stably maintained, and the separation work for separating the connectors 10, 50 to be safely and easily carried out. The plurality of notches 82 formed in the surrounding wall section 60, 64 of the body 52 of the connector 50 are disposed in the mounting area of the connector 50 on the circuit board R (that is, area occupied by the connector system 90), so that they do not influence the high density mounting of the circuit board R.

In the above construction, as shown in Fig. 10, the plurality of notches 82 provided in the surrounding wall section 60, 64 of the body 52 of the connector 50 are preferably disposed at symmetrical positions with respect to the centerline 52c bisecting the body 52 in longitudinal direction. Also, as seen from the body 12 of the connector 10, the plurality of notches 82 are preferably disposed at symmetrical positions with respect to the centerline 12c bisecting the body 12 in transverse direction. By forming the plurality of notches 82 at positions symmetrical to each other with respect to a given centerline defined on the connector body 52, an article picking-type tool such as a tweezer (not shown) can be used to exert a balanced separation force to the connector 10 to separate it from the receptive recess 66 of the connector 50. As a result, damage to the connectors 10, 50 can be more effectively prevented. In the embodiment shown, a pair of notches 82 are provided at positions adjacent to the first support section 58 of the body 52 of the connector 50. Therefore, a cut-away 84 is formed at corresponding position of the shield member 56 so as to permit a tool, etc. to be inserted into the notch 82. Desired number of notches 82 can be provided at desired positions in the connector body 52 by making such structural contrivance as necessary. In case where, as in the embodiment shown, the surrounding wall section 60, 64 of the body 52 has a set of mutually opposing wall portions (for example, a part of the second support section 60 adjacent to the first support 58 and the edge wall section 64 opposing thereto), the plurality of notches 82 may be provided at respective appropriate positions on these wall portions, not limited to the above described symmetrical positions. With such construction, it is also possible to use an article picking-type tool to exert a stable separation force to the counterpart connector by multi-point picking of three points or more to separate it from the connector.

The present invention has been described above with reference to preferred embodiments thereof. However, the present invention is by no means limited to the construction of above-described embodiments, and various modifications can be made to the above embodiments. For example, as shown in Figs. 11 and 12, in the cable connector 10, the abutting portion 44c of the shield member 44 between the two attaching portion 44b fitted to the body 12 may have same bent shape as the attaching portion 44b. In this case, each abutting portion 44c is abutted in good electrical conduction to the inner surface of the second contact piece 34b of each ground-contacting section 34 of the grounding member 30 exposed on the fitting section 40 of the body 12, and the shield member 44 is thereby electrically connected to the grounding member 30 (Fig. 12(b)).

The body 12 of the connector 10 may include one or more beam portion 86 so as to traverse the opening 38having the cable-connecting section 32 of the grounding member 30 (Fig. 1 l(b)). With such construction, rigidity of the connector body 12 can be increased and fixing strength of the grounding member 30 to the connector body 12 can be improved.

Claims

CLAIMS:

1. A connector comprising an electrical insulating body, a terminal element supported on the body and adapted to be connected to a core conductor of a cable, and a grounding structure provided on the body while being insulated from the terminal element and adapted to be connected to a shield layer of the cable, characterized in that: said grounding structure comprises a grounding member fixed to said body; and that said grounding member is disposed along a surface, at a side proximate to said body, of the shield layer of the cable with the core conductor of the cable being connected to said terminal element, and is connected to the shield layer.

2. A connector as set forth in claim 1, wherein said grounding member includes a cable-connecting section, adapted to be connected to the shield layer of the cable, and a ground-contacting section capable of coming into conductive contact with a corresponding grounding element of a counterpart connector.

3. A connector as set forth in claim 1, adapted to be connected to a plurality of coaxial cables respectively including core conductors and shield layers covering the core conductors, wherein a common grounding plate is connected to the shield layers of the plurality of coaxial cables, said grounding member being fixed and connected to the grounding plate.

4. A connector as set forth in claim 3, wherein said grounding member includes a cable-connecting section, having a rectangular plate shape similar to a shape of said grounding plate and adapted to be connected to said grounding plate, and a pair of ground-contacting sections extending respectively from opposite longitudinal ends of said cable-connecting section and capable of coming into conductive contact with a corresponding grounding element of a counterpart connector.

5. A connector as set forth in any one of claims 1 to 4, wherein said grounding member is integrally fixed to said body through insert molding.

6. A connector as set forth in any one of claims 1 to 5, further comprising a shield member attached to said body while being insulated from said terminal element; wherein said shield member is disposed at a side opposite to said grounding member relative to the shield layer of the cable with the core conductor thereof being connected to said terminal element, and is connected to said grounding member.

7. A connector comprising an electrical insulating body including a receptive recess for detachably receiving a counterpart connector, and a terminal element supported on the body and adapted to be connected to a conductor of a circuit board, characterized in that: said body comprises a terminal element supporting section for supporting said terminal element and a surrounding wall section cooperating with said terminal element supporting section to define said receptive recess, wherein a plurality of notches, each opening to, and communicating with, said receptive recess, are dispersedly provided in said surrounding wall section.

8. A connector as set forth in claim 7, wherein said surrounding wall section of said body includes a set of wall portions opposing each other, and wherein said plurality of notches are provided in each of the set of wall portions.

9. A connector as set forth in claim 7 or 8, further comprising a shield member attached to said body while being insulated from said terminal element, wherein said shield member includes a grounding element capable of coming into conductive contact with a grounding member of a counterpart connector.

10. A connector system comprising a mutually attachable and detachable combination of a connector as set forth in any one of claims 1 to 6 and a connector as set forth in any one of claims 7 to 9.