Plug connector and socket connector

Abstract: A high speed transmission connector comprises a plug connector (63) and a socket connector (135) to be fit to each other along a first direction. The plug connector (65) comprises a socket connector fitting portion provided at an end of the insulator so as to be fit to the socket connector along the first direction and an FPC fitting portion provided at the other end of the insulator so as to be fit to FPC along the first direction. The socket connector comprises a plug connector fitting portion to be fit to the plug connector along the first direction and a PCB connecting portion to be soldered onto a PCB. The FPC fitting portion contains a plurality of contacts. Each comprises a pair of first plug contacts (103) arranged along a second direction perpendicular to the first direction and a second plug contact (95) disposed between the pair for sending a ground signal. Both are disposed in the insulator. The plug connector contains a plug side signal contact and a plug side ground contact. Both of contacts are provided at the socket connector fitting portion to be fit to the plug connector fitting portion. The plug connector fitting portion has a first socket contact (143) coming into contact with the plug side signal contact and a second socket contact (163) coming into contact with the plug side ground contact. The first and the second socket contacts enclose the socket connector fitting portion along a direction perpendicular to the first direction such that they oppose each other along a direction perpendicular to the first direction.

Description: BACKGROUND OF THE INVENTION This invention relates to a two-piece electrical connector for connecting a flexible flat cable (EFC) or a flexible printed circuit board (FPC) to a connection object such as a printed circuit board (PCB) and, in particular, to such a two-piece connector having metallic shells for electromagnetic shielding which is adaptive for high-speed transmission. A two-piece electrical connector of the type described is used in, for example, notebook type computers. Such a two-piece electrical connector comprises a cable connector member mounted on a FPC or FFC (which will collectively be referred to as "FPC") and a mating connector member mounted on a PCB. The cable connector member is mated with the mating connector member to establish the connection between the FPC and the PCB. In the prior art, the FPC generally comprises an insulator sheet or film having two laminated layers in which a plurality of signal conductors are embedded for transferring electric signals. A ground pattern is generally coated on at least one outer surface of the insulator film as an electro-magnetic shielding in order to suppress the electro-magnetic interference generating noise. JP-A-9 232039 discloses such a two-piece electrical which has metallic shells mounted on the outer surface thereof for protecting the connector from the noise. A cable connector member in the known connector is provided with a cable fixture for fixing an end of the FPC to the cable connector member itself for establishing electrical and mechanical connection of the FPC and the cable connector member. The cable fixture is rotatably mounted on a connector housing of the cable connector member. That is, when the cable fixture is positioned at a first position or an open position, the one end of the FPC is loosely insertable in the cable connector member. When the cable fixture is angularly rotated to a second position or a fixing position, the one end of the FPC is pressed onto contact terminal portions in the cable connector member by the cable fixture so that the FPC is mechanically and electrically connected to the cable connector member. The cable connector has a metallic shell covering an outer surface of the connector housing and another metallic shell covering the cable fixture. In the known connector, two pieces of different metallic shells are required for the cable connector member and another different metallic shell is required to a mating connector. Thus, metallic shells of three different shapes must be prepared and assembled to the two different connector members. This results in a high cost, complicate assembling operation, and difficulty of management and quality control of parts. Further, in the known connector, the cable fixture is rotatably mounted on the connector housing. Therefore, the connector requires an increased mounting space in order to allow the rotation of the cable fixture. This results in difficulty of high density disposition of electric parts including the known connector. In order to resolve the problems, a Japanese patent application No. 9-81129 (81129/1997) filed March 31, 1997 (published as JP-A 10-284201), proposes a two-piece electrical connector where fixing a FPC to a cable connector member is performed by a slider inserted together with one end portion of the FPC into a connector housing. A metallic shall fixedly supports the slider therein and is slidably fitted on the connector housing for providing the electro-magnetic shielding. Insertion and removal of the slider for the connector housing are performed by sliding operation of the metallic shell on the connector housing. The connector proposed in the copending application described above will be referred to as a "prior connector", hereinafter. However, both of the known connector and the prior connector still have various problems as described below. The mating connector member mating with the cable connector member has a plurality of contacts of a pin type. There is a problem that the pin type contact is easy to bend when the cable connector member is fitted thereto or removed therefrom. Further, the cable connector member has contacts which have complicated structure. In particular, contacts of the prior connector has a complicated box-shaped structure for receiving the pin type contact. Therefore, it is difficult to establish the impedance matching. The impedance mismatching causes a problem for the high speed transmission. Further, some of the contacts in cable connector member are arranged to come into contact with the ground pattern on the main surface of the FPC but has no electrical relation with the ground plate pattern on the back surface of the FPC. As a result, there is a disadvantage that grounding is incomplete. Further, since ground ones of contacts of the mating connector member are not connected to the shell, ground condition is not maintained excellent if a ground signal flows through the ground contacts in the socket connector. Still further, the cable connector member uses a rotating insulator or a slide insulator, and therefore, the number of the parts increases correspondingly. Further, since the height of the cable connector needs correspondngly an additional height for permitting rotation of the rotating insulator or the fitting of the slide insulator, there is such a disadvantage that the entire height is not reduced. From US patent 4,747,787 a connector is known comprising a first plug and a second plug. The first plug has a pin shape for connecting signal lines of a ribbon cable to a substrate, such a printed circuit board. The second plug has a plate shape for connecting and gathering ground lines of the ribbon cable to the substrate. Signal lines and ground lines are connecting to the first and the second plugs with separating into individual lines. SUMMARY OF THE INVENTION Accordingly, it is a first object of the present invention to provide a plug connector having a small change of impedance due to a contact. Further, it is a second object of the present invention to provide a plug connector capable of transmitting a ground signal securely and completely when the FPC is connected to a ground pattern. Further, it is a third object of the present invention to provide a plug connector having a contact highly resistant to buckling deformation which may occur upon insertion or removal. Still further, it is a fourth object of the present invention to provide a plug connector whose height can be reduced and in which the number of the parts can be minimized. Still further, it is a fifth object of the present invention to provide a plug connector having a structure for preventing the FPC from being loosened easily after the FPC has been fit and having a structure facilitating an operation of the slider for removing the FPC by using such a jig as a screwdriver. It is a sixth object of the invention to provide a socket connector highly resistant to buckling or deformation which may occur when the counter connector is inserted or removed. It is a seventh object of the invention to provide a socket connector having an excellent ground condition and allowing an accurate and complete grounding. It is an eighth object of the invention to provide a socket connector in which impedance matching is easy. It is a ninth object of the invention to provide a socket connector in which the counter connector is easy to introduce, an end thereof making contact with the ground plate is difficult to buckle or deform, and a strength thereof is intensified so as to reduce a height of the product. It is a tenth object of the invention to provide a socket connector coping with a high speed transmission and having a small size and excellent operability. It is an eleventh object of the invention to provide a high speed transmission connector comprising a plug connector and a socket connector having the above described advantages. Such objects are solved by a plug connector with the features of the independent claim 1, by a socket connector with the features of the independent claim 9, and by a high speed transmission connector with the features of the independent claim 13. Preferred developments of the invention are given in the respective dependent claims. BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view showing a plug connector according to an embodiment of the present invention; FIG. 2 is a perspective view having a partial sectional view taken along the line II-II of the plug connector of FIG. 1; FIG. 3 is a perspective view having a partial sectional view taken along the line III-III of the plug connector of FIG. 1; FIG. 4 is a perspective view showing only a ground plate shown in FIGS. 1 to 3; FIG. 5 is a perspective view showing a state in which the slider portion of the plug connector shown in FIGS. 1 to 4 is released; FIG. 6 is a perspective view having a partial sectional view taken at the same position as FIG. 2 of the plug connector of FIG. 5; FIG. 7 is a perspective view having a partial sectional view taken at the same position as FIG. 3 of the plug connector of FIG. 5; FIG. 8 is a perspective view showing a fitting state between the plug connector shown in FIGS. 1 to 7 and FPC; FIG. 9 is a perspective view having a partial sectional view taken at the same position as FIG. 2 of the plug connector shown in FIG. 8; FIG. 10 is a perspective view having a partial sectional view taken at the same position as FIG. 3 of the plug connector shown in FIG. 8; FIG. 11 is a partial perspective view showing mainly a locking portion for an insulator, provided in a shell of the plug connector according to an embodiment of the present invention; FIG. 12 is a partial plan sectional view showing mainly a locking portion for an insulator, provided in a shell of the plug connector according to the embodiment of the present invention; and FIG. 13 is a perspective view showing a loosening stopper mechanism provided on a shell as a loosening stopper means of the plug connector according to the embodiment of the present invention; FIG. 14 is an appearance view of a socket connector according to the embodiment of the present invention; FIG. 15 is a partially broken, partial sectional view of the socket connector of FIG. 14; FIG. 16 is a perspective view showing a ground plate of FIGs. 14 and 15; FIG. 17 is a perspective view showing a modification of the ground plate of FIG. 16; FIG. 18 is a diagram showing an example of a section of the counter plug connector shown in FIG. 1; and FIG. 19 is a partial sectional view showing a condition in which the plug connector shown in FIG. 1 or 18 is fit to the socket connector shown in FIG. 14. DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 to 19, description will be made as regards a two-pair connector according to an embodiment of the present invention. The two-pair connector comprises a cable connector member or a plug connector 63 and a mating connector member of a socket connector 135. The plug connector 63 has a socket connector fitting portion 65 and an FPC fitting portion. The socket connector fitting portion 65 is to be fit to a socket connector serving as a substrate side connector (not shown) along a first direction which is a fitting direction. The FPC fitting portion 67 is to be fit to the FPC or FFC along the same first direction. Both of the fitting portions are provided on both ends in the fitting direction which is the first direction. Here, for convenience for description, two opposite sides of the plug connector 63, that is a side of the FPC fitting portion 67 and another side of the socket connector fitting porion 65 , will be called "front side" and "rear side", respectively, relative to the first direction. The plug connector 63 comprises an insulator 69 made of insulating material, a shell 71 for covering the insulator 69, a plurality of contacts 73 (hereinafter referred to as "first plug contact") arranged in the width direction which will be referred to as a second direction perpendicular to the first direction and inserted in the insulator 69, and a ground plate 75 inserted into the insulator 69 in such a manner that it has no contact with any of the first plug contacts 73. Since this first plug contact 73 is formed of a leaf spring, a change of its impedance produced when connected is small. The insulator 69 has a horizontal substantially Y-shaped section produced by overlapping ends of an upper plate 77, a middle plate 79 and a lower plate 81 in a third direction perpendicular to the first and the second directions, that is, in the thickness direction, such that the respective plates stagger from each other horizontally. A bottom end of the upper plate 77 has protrusions extending in the first direction and forming an accommodating groove 83 for accommodating a contact which is one end side of the FPC. The shell 71 is formed in the form of a box made of conductive material having an opening at its rear end. At the front end, an opening 87 is formed which has a slider portion 85 composed of a flat plate folded backward. A front end portion of the insulator 69 is projected into the opening 87. An FPC fitting portion 67 into which the FPC is to be inserted is formed by the slider portion 85 and a front end portion of the upper plate 77 of the insulator 69. Further, on both sides of the slider portion 85, stopper pieces 89 are provided as stopping means which prevents the FPC (not shown) from slipping out as well as guiding an insertion of the FPC. Further, on both sides of the top surface of the shell 71, spring pieces 91 are provided which are formed by incision. As best shown in FIG. 2, each of the first plug contact s 73 has a single sheet simple leaf spring structure having a small change of impedance. The first plug contact comprises a pressed portion 93, an FPC contact portion 95, and a contact contacting portion 97. The pressed portion 93 is pressed and supported by the insulator 69. The FPC contact portion 95 extends forward from the pressed portion 93 so as to project into the FPC fitting portion 67, whose end is curved in the form of U shape. The contact contacting portion 97 extends backward from the pressed portion 93 along a surface of the insulator 69 and is bent downward along a rear end slope of the insulator 69. The plurality of first plug contacts 73 is spaced in the width direction. Particularly being conscious of the operation signal, two pieces of the first plug contact 73 are paired and in this example, seven pairs are provided. The contact contacting portion 97 is inserted in a groove 99 provided on the top surface of the middle plate 79 of the rear end of the insulator 69. In the connector fitting portion 65 to be fit to the socket connector, on the back surface of the contact 73 there is placed a ground plate 75 nipping the insulator 69. The contact contacting portion 97 and the ground plate 75 are provided as if they nip this insulator 69 and are formed in the form of a single plate, so that a non-pin structure connector fitting portion 65 having no pin is formed at the rear end of the plug connector 63. As best shown in FIG. 3, the front side of the ground plate 75 is disposed such that it is nipped between the slider portion 85 and insulator 69 and the rear portion thereof is exposed on the bottom surface of the rear end of the insulator 69, so that it extends up to an protrusion 101 projecting downward of the middle plate 79 of the insulator 69. Further, as to the ground plate 75, its cut piece formed by incision is erected from a plate surface thereof and bent forward and its front end is bent in the form of U shape like the FPC contacting portion 95 so as to form a contact type spring contacting portion 103 (hereafter referred to as "second plug contact") projecting into the FPC fitting portion 67. This second plug contact 103 of the ground plate 75 is provided so as to make a contact with the ground pattern of the front side pattern of the FPC and disposed between the FPC contacting portions 95 of the first plug contacts 73 of each pair. As shown in FIG. 4, the spring contacting portions (second plug contact) 103 to be fit to the ground pattern of the front side pattern of the FPC are disposed at several positions. This spring contacting portion 103 is disposed between the first plug contacts 73 of each pair as described previously and the spring contacting portion consisting of the second plug contact 103 is so constructed as to nip the fitting FPC so that it makes contact with the ground patterns of the front and back sides of the FPC, thereby transmitting the ground signal of the FPC securely. Further, since the socket connector fitting portion 105 to be fit to the socket connector (not shown) is of a single sheet, it is capable of transmitting the ground signal through a wide area. Additionally, an opposite side to the socket connector fitting portion 105 side becomes a front piece 107 suspending vertically. As shown in FIGS. 5 to 7, under a released state of the plug connector, by sliding the shell 71 forward relative to the insulator 69 on which the first plug contact 73 and ground plate 75 are mounted, the plug connector 63 becomes in the released state. Referring to FIGS. 8 to 10, in the released state shown in FIG. 6, the FPC 111 is inserted and next the shell 71 is pushed to the insulator 69 side. A front end of a bottom portion 109 of the shell 71 comes into contact with a projecting step portion 117 on the bottom of the insulator 69, so that the motion of the shell 71 is blocked, thereby completing the fitting. At this time, as best shown in FIG. 9, the surface pattern 113 of the FPC 111 comes into contact with the FPC contacting portion 95 of the first plug contact 73. On the other hand, the back surface pattern 115 of the FPC 111 comes into contact with the slider portion 85 of the shell 71, so that it is electrically connected to the ground plate 75 through the front piece 107 of the ground plate 75 contacting an inner lower surface of the shell 71. Further, as best shown in FIG. 10, when the slider portion 85 of the shell 71 penetrates under the FPC 111, the FPC 111 is pushed upward, so that the spring contacting portion 103 of the ground plate 85 comes into contact with the surface pattern 113 of the FPC 111. Further in the similar manner being described previously, the back surface pattern 115 of the FPC 111 comes into contact with the slider portion 85 of the shell 71, so that it is electrically connected to the ground plate 75. When the FPC is fit to the shell 71, the slider portion 85 makes electrical contact with the ground pattern 115 of the back side of the FPC 111, so that the ground signal of the FPC 111 can be transmitted securely. As shown in FIGS. 11 and 12, a locking portion 119 is formed on the shell 71 and serves as a locking means. The locking portion 119 contains a spring portion 121, a rectangular portion 123, and a spring deflection stopper portion. The spring portion 121 is formed near the side portion of the shell 71. The rectangular hole portion 123 is formed in the spring portion 121. The spring deflection stopper portion 125 is formed outside the spring portion 121 of the shell 71. Furthermore, the locking portion 119 is provided with a protrusion 127 on the side surface of the insulator 69. As best shown in FIG. 12, by inserting the protrusion portion 127 of the insulator 69 into the hole portion 123 of the spring portion 121 when the FPC is fit, the shell 71 and insulator 69 are prevented from moving, that is, locked. If they are once locked, even if the FPC 111 is pulled relative to the insulator 69, it cannot be loose. However, as shown in FIG. 12, by inserting such a jig 129 as a screwdriver into a gap 131 formed at the rear on both sides of the plug connector 63 and moving the spring portion 121 downward outside in FIG. 10, the engagement between the hole portion 123 of the spring portion 121 and the protrusion 127 of the insulator 69 is released, so that the shell 71 can slide, thereby making it possible to release the FPC 111 easily. Further, as shown in FIG. 13, a loosening stopper mechanism is constructed, in which loosening stopper portions 133 projecting in the width direction are formed on the front end at both sides of the FPC 111. The stopper pieces 89 is formed on both sides of the shell 71. When the FPC is fit, the stopper pieces 89 come into contact with the loosening stopper portions 133, thereby preventing the FPC 111 from being loose. In the above, although the plug connector of an embodiment of the present invention has been described only with respect to the FPC fitting portion to be fit to the FPC 111, it is apparent that this FPC fitting portion can be similarly used also for the EFC. As described above, according to the present invention, since the contact is formed of a single leaf spring, it is possible to provide a plug connector in which a change of impedance is small. Further, according to the present invention, since a single ground plate is in contact with the ground pattern on one surface of the FPC and that on the other surface of the FPC, it is possible to provide a plug connector capable of transmitting the ground signal securely and completely. Furthermore, according to the present invention, sine the connector fitting portion to be fit to the socket connector has a non-pin structure, it is possible to provide a plug connector highly resistant to buckling which may occur upon fitting or removal. Still further, according to the present invention, since the second plug contact of the ground plate to be in contact with the front side ground pattern of the FPC is so structured as to nip the FPC by itself, it is possible to provide a plug connector having a high contact reliability. In addition, according to the present invention, since the shell has a function of the slider portion to achieve ZIF type fitting and this function is carried out without any other help, the thickness of the product can be reduced and it is possible to provide a plug connector whose number of parts can be minimized. Further, according to the present invention, since the shell having a function as the slider portion has every locking function, after the FPC is fit, it cannot be loosened easily and, in addition, by using such a jig as a screwdriver, it is easy to operate the slider to remove the FPC. Next, the socket connector of the embodiment of the present invention will be described with reference to FIGs. 14-19. Referring to FIGs. 14 and 15, a socket connector 135 has a plug connector fitting portion 137 which is fit to the aforementioned plug connector 63 along a first direction, provided at a front end thereof and a substrate connecting portion 139 to be soldered to a substrate, provided at a rear end thereof. For convenience of description, along the first direction, a side of the plug connector fitting portion 137 of the socket connector 135 is called front side and a side of the substrate connecting portion 139 to be connected to a substrate is called rear side. The socket connector 135 comprises an insulator 141 having an L-shaped section, a signal socket contact 143 (hereinafter referred to as first socket contact) implanted in the insulator 141, a ground plate or ground contact 145, and a shell 147 provided around the insulator for serving as a shield ceiling of the socket. The insulator 141 has a top plate 149 and a bottom plate 151 provided at a rear end of the socket connector 135 integrally with the top plate 149. The first socket contact 143 is implanted between the top plate 149 and bottom plate 151. The shell 147 is of box type and has an opening 153 at a front end thereof, and comprises a top plate 155 provided so as to cover the insulator 141, substrate fixing portions 157 provided at both ends in width direction of a second direction perpendicular to the first direction so as to protrude in a U-shape, and a bottom plate 159. The substrate fixing portion 157 acts as a soldering portion for a PCB and the shell 147 has an electrical function for grounding. In the shell 147, the bottom plate 159 has a folding portion 161 in which a front end thereof is folded so as to form double layers, a cutout portion 165 cut out corresponding to a contact portion 163 of the ground contact 145 which will be described in detail later and a lower bottom portion 181. The folding portion 161 introduces a socket connector fitting portion of the plug connector which is a counter connector of the socket connector 135 and intensifies the strength. The cutout portion 165 of the shell 147 protects a front end of the contact portion 163 of the ground plate 145 which will be described later. As evident in FIG. 15, the first socket contact 143 which is a signal contact has a spring elastic property and a narrow sheet-like configuration corresponding to the impedance matching. The first socket contact 143 comprises a contact portion 167 one end of which is accommodated in the plug connector fitting portion and bent in a V-shape so as to make contact with the counter contact, a supporting portion 169 extending from the contact portion 167 backward of the connector and fixed to the insulator 141 such that it is supported thereby, and a soldering terminal portion 171 which extends from the supporting portion 169 backward of the socket connector 135 along the first direction and is bent to extend along a third direction perpendicular to the first and second directions and further is bent in the first direction which is a horizontal direction so as to extend horizontally, providing a means for soldering on a PCB. As described above, the signal contact 143 has a simple sheet-like structure, thereby making it possible to achieve impedance matching. Referring to FIG. 16, the ground plate 145 is formed by punching and pressing a single conductive material plate, constituted of a link portion 173 extending along the second direction which is a width direction of the socket connector 135, soldering terminal portions 175 bent from the link portion 173 and extending backward, fixing portions 177 which extend upward from the same position as the soldering terminal portion 175 and is bent forward providing a means for fixing to the insulator, contact base portions 179 disposed between the soldering terminal portion 175 and fixing portion 177 and have a spring elastic property, and pairs of the contact portions 163 (second plug contact) extending from each of the contact base portions 179 in parallel. Referring to FIGs. 14 and 15, a pair of the first socket contacts 143 which are signal contacts are disposed in parallel, so that concretely, seven pairs thereof are supported by the insulator 141. That is, the first socket contacts 143 of the socket connector 135 transmit seven pairs of differential signal. In the plug connector fitting portion 137 of the socket connector 135, the contact portion 167 of the first socket contact 143 is provided on a side of the top plate and the second socket contact 163 formed of the contact portion of the ground plate 145 is provided on the bottom side opposing the contact portion 167 of the first socket contact 143 in the third direction. The second socket contact 163 is accommodated in the cutout portion 165 of the shell 147. When the plug connector is fit, the fitting portion of the plug connector is nipped by the contact portion 167 of the first socket contact 143 and the second socket contact 163 from up and down. The soldering terminal portions 175 of the ground plate 145 are disposed so as to enclose the soldering terminal portions 171, 171 of the first socket contact 143 for signaling protruded backward of the socket connector 135 along the second direction (width direction of the socket connector 135). By protruding the soldering terminal portion 175 from the ground plate 145 as much as possible, ground condition can be improved. Referring to FIG. 17, in a ground plate 145' according to a modification, fixing portions 177' are formed on both ends of a link portion 173', soldering terminal portions 175' extend from the top of the link portion 173' and like the ground plate shown in FIG. 16, contact base portions 179' extend from a bottom of the link portion 173' and further, contact portions 163', 163' are formed so as to be continuous with the contact base portion 179'. As shown in FIG. 18, the plug connector 63 has a FPC fitting portion 83 at one end thereof and a socket connector fitting portion 65 at the other end thereof. Reference numeral 111 denotes FPC connected and locked to the FPC fitting portion. Next, fitting between the socket connector and plug connector according to the embodiment of the present invention will be described with reference to FIG. 19. As shown in FIG. 19, in the plug connector fitting portion, the contact portion 167 of the first socket contact 143 forming a pair with the other one, which is a signal contact of the socket connector 135 and the second socket contact 163 which is a contact portion of the ground plate 145 of the socket connector 135 are disposed along the third direction so as to oppose each other. When the socket connector fitting portion of the plug connector 63 and the plug connector fitting portion of the socket connector 135 are fit to each other, the plug connector 63 is nipped between the contact portion 167 of the first socket contact 143 and second contact portion 163 disposed along the third direction so as to oppose each other in the plug connector fitting portion. At this time, the contact portion 95 of the first plug contact which is a signal contact of the plug connector 63 comes into contact with the contact portion 167 of the first socket contact which is a signal contact of the socket connector 135. On the other hand, the ground contact portion 105 of the ground plate 75 of the plug connector 63 comes into contact with the contact portion 163 of the ground plate 145 of the socket connector 135. Further, a back side of the contact proximal end of the ground plate 145 of the socket connector 135 comes into contact with the lower bottom portion 181 of the shell 147. As described, in the socket connector 135 according to the embodiment of the present invention, the contact portion 35c of the signal contact 143 and contact portion 163 of the ground plate 145 are located up and down in the plug connector fitting portion, thereby forming a non-pin type socket connector which is highly resistant to buckling or deformation which may occur when the plug connector 63 is inserted or removed. Further, the ground plate 145 has a plurality of the contact portions as a ground fitting contact portion and the plurality of the soldering terminal portions 175 are formed on a single plate as a single part, ground condition is excellent and grounding is accurate and complete. Further, the contact portions 163 of the ground plate 145 are in contact with the shell 147 through plural points, ground condition can be further maintained excellently. Because the signal contact 143 of the socket connector 135 according to the embodiment of the present invention is of a simple sheet-like configuration, impedance matching is easy. Because the bottom portion of the side to which the plug connector 63 is to be fit of the shell 147 has the folding portion 161, it can introduce the counter connector easily. Further because the cutout portion 165 is provided on the bottom, it is possible to prevent the contacting end of the plug connector from being buckled or deformed by the ground plate 145. Further, the folding portion 161 of the shell 147 intensifies the strength and eliminates the necessity of the insulator 141 at this portion, thereby making it possible to reduce the height of this product. Because according to this invention, there is provided a non-pin type socket connector in which the signal contact and ground plate fitting contact portion are located up and down, a socket connector highly resistant to buckling or deformation which may occur when the counter connector is inserted or removed can be provided. Further, because according to this invention, the ground plate has a plurality of contact portions to achieve ground fitting contact and a plurality of the soldering terminals as a single plate (as a single part), ground condition is excellent and grounding is accurate and complete. Further, because the spring portion of the ground contact portion comes into contact with the shell through plural points, it is possible to provide a socket connector having an excellent ground condition. Further, because, according to this invention, the signal contact is of a simple sheet-like structure, it is possible to provide a socket connector in which impedance matching is made easy. Further, because according to this invention, the folding portion is provided at a portion to be fit to the counter plug connector of the shell, the counter connector can be introduced easily and additionally, the cutout portion makes it difficult for the contacting end portion to be buckled or deformed by the ground plate. The folding portion intensifies the strength of the socket connector and eliminates the necessity of the insulator at this position thereof, thereby reducing the height of the product. Therefore, according to this invention, it is possible to provide a socket connector capable of meeting high speed transmission and having a small size and an excellent operability. Further, according to this invention, it is possible to provide a high speed transmission connector comprising a plug connector and socket connector having the above described advantages.

Claims: A plug connector (63) comprising: a counter connector fitting portion (65) to be connected to a counter connector along a first direction provided at one end of an insulator (69), and a FPC fitting portion (67) to be connected to a FPC (111) or FFC similarly along the first direction and elongated along a second direction intersecting to said first direction at the other end of the insulator (69), wherein said FPC fitting portion (67) comprises a plurality of contacts disposed within said insulator (69), each of said contacts consisting of a pair of two first plug contacts (73, 95) arranged in said second direction and a second plug contact (103) arranged between said pair of first plug contacts (73, 95) for transmitting a ground signal, said pair of first (73, 95) and said second (103) plug contacts being plate springs and contacting to said FPC or FFC in a third direction intersecting to said first and said second directions, said one end of said insulator (69) being formed into a plate shape at one end, each of said first plug contacts (73, 95) having an extending portion extending in the first direction on said one end of said insulator (69), said counter connector fitting portion (65) being formed in the form of a plate which comprises said extending portion, said counter connector fitting portion (65) having a non-pin structure. The plug connector according to claim 1, wherein said second plug contact (103) is formed on a ground plate (75) made of a single conductive plate and/or said insulator (69) and said ground plate (75) being opposed to said extending portion in a third direction intersecting to said first and said second directions opposed to said extending portion through said insulator (69). The plug connector according to claim 1 or 2, wherein said counter connector fitting portion (65) is formed as a plug side fitting portion of a non-socket. The plug connector according to claim 2 or 3, wherein said ground plate (75) has such a shape that it can sandwich by itself the FPC through said second plug contact (103). The plug connector according to one of claims 1 to 4, further comprising on its periphery a shell (71) slidably movable in said first direction, wherein said shell (71) has a slider portion (85) for moving said FPC in said first direction so as to bring the FPC into a contact with said contacts when the FPC is connected, said shell (71) preferably has a loosening stopper means (133) for preventing said FPC from being loosened when it is connected and/or said shell (71) is formed of an integral part with said slider portion (85), and/or said slider portion (85) is made of sheet-like electrical material formed only of a single part. The plug connector according to claim 5, further comprising a locking means (119) for preventing said FPC from being loosened, wherein said locking means (119) has a protrusion portion (127) projecting in said second direction of said insulator (69) and a spring portion (121) having a hole (123) provided on said shell (71) correspondingly to the protrusion (127) of said insulator, said locking means (119) being also formed so as to be easily releasable by using a jig (129). The plug connector according to claim 1, wherein each of said second plug contacts (103) has a surface contact portion provided in a FPC fitting portion (67) and a connecting portion connected to a ground plate (75) opposite to said surface contact portion, said surface contact portion and said ground plate sandwiching the FPC (111) to contact with ground patterns formed on one surface and another surface of the FPC (111), respectively, whereby transmissions of ground signals are performed reliably and perfectly. The plug connector according to claim 1, wherein said conduct plate and said second plug contacts (103) are formed with a single ground plate (75), said extending portion of said first plug contacts (73, 95) being disposed on one surface of said counter connector fitting portion (65), said ground plate (75) being extended opposed to said extending portion through said insulator (69) and disposed on another surface of the counter connector fitting portion (65). A high speed transmission connector comprising a plug connector (63) and a socket connector (135) to be connected to each other along a first direction, said plug connector (63) comprising a counter connector fitting portion (65) to be connected to a counter connector (135) along a first direction and provided at one end of an insulator (69), and a FPC fitting portion (67) to be connected to a FPC (111) or FFC similarly along the first direction and elongated along a second direction intersecting to said first direction at the other end of the insulator (69), said socket connector (135) comprising a plug connector fitting portion (137) to be connected to the plug connector (63) along the first direction and a substrate connecting portion (139) to be soldered onto a substrate; said FPC fitting portion (67) containing a plurality of contactors each comprising a pair of two first plug contacts (73, 95) arranged along said second direction perpendicular to the first direction and a second plug contact (103) disposed between the pair first plug contacts (73, 95) for sending a ground signal, said pair of first (73, 95) and said second (103) plug contacts being plate springs and contacting to said FPC or FFC in a third direction intersecting to said first and said second directions, said one end of said insulator (69) being formed into a plate shape at one end, each of said first plug contacts (73, 95) having an extending portion extending in the first direction on said one end of said insulator (69), said counter connector fitting portion (65) being formed in the form of a plate which comprises said extending portion, said counter connector fitting portion (65) having a non-pin structure, said plug connector (63) containing a plug side signal contact and a plug side ground contact, both provided at the socket connector fitting portion (65) to be connected to the plug connector fitting portion (137), said plug connector fitting portion (137) having a first socket contact (143, 167) coming into contact with the plug side signal contact and a second socket contact (145, 163) coming into contact with the plug side ground contact; said first and said second socket contacts being disposed so as to enclose the socket connector fitting portion (65) along a forth direction perpendicular to the first direction such that they oppose each other along a fifth direction perpendicular to the first and forth directions. The high speed transmission connector as claimed in claim 9, wherein said first socket contact (143, 167) has a contact portion (167) for elastically contacting with the counter connector's signal contact and a soldering terminal portion (171) to be soldered onto a substrate, said second socket contact (145, 163) containing a contact portion (163) of a ground plate (145) for elastically contacting with the counter connector's ground contact, said ground plate (145) further having a soldering terminal portion (175) to be soldered to a substrate. The high speed transmission connector as claimed in claim 9 or 10, wherein said second plug contacts (103) are formed on a ground plate (75) formed of a single conductive plate. The high speed transmission connector as claimed one of claims 9 to 11, wherein said first plug contact (73, 95) has an extending portion extending along the first direction, said counter connector fitting portion (65) having a sheet-like structure comprises said extending portion, said insulator (69) and said ground plate (75) opposing said extending portion via said insulator (69) in a third direction perpendicular to the first and second directions. The high speed transmission connector according to claim 9, wherein each of said second plug contacts (103) has a surface contact portion provided in a FPC fitting portion (67) and a connecting portion connected to a ground plate (75) opposite to said surface contact portion, said surface contact portion and said ground plate (75) sandwiching the FPC (111) to contact with ground patterns formed on one surface and another surface of the FPC, respectively, whereby transmissions of ground signals are performed reliably and perfectly. The high speed transmission connector according to claim 9, wherein said conduct plate and said second plug contacts (103) are formed with a single ground plate (75), said extending portion of said first plug contacts (73, 95) being disposed on one surface of said counter connector fitting portion (65), said ground plate (75) being extended opposed to said extending portion through said insulator (69) and disposed on another surface of the counter connector fitting portion (65).

Inventors: HAYASHI KOJI, HAYASHI, KOJI, Hayashi, Koji, c/o Japan Aviation Electr. Ind.Ltd
Applicants: JAPAN AVIATION ELECTRON, JAPAN AVIATION ELECTRONICS INDUSTRY, LIMITED
Application year: 1999
Main classification: H01R12
IPC codes: H01R13, H01R12