Abstract:
A modular connector comprises an insulating housing ( 100 ) having a plugging portion for plugging with a mating connector, a plurality of contact elements ( 201-208 ) supported by the insulating housing, the contact elements each having a contact section ( 201   a   -208   a ) arranged in the plugging portion, an intermediate section ( 201 B- 208 B) secured to the insulating housing, and a connection section ( 201 C- 208 C) extending from the intermediate section, a pair of the contact elements ( 201, 208 ) on opposite ends being twisted to intersect each other in the intermediate sections, the other pairs of the contact elements ( 202-207 ) being arranged such that the distance between adjacent contact elements decreases in the intermediate sections and increases in the connection sections.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to modular connectors and, particularly, to a modular jack type connector. 
     2. Description of the Related Art 
     Modular connectors are widely used in communications equipment. A modular connector comprises an insulating housing having a plugging portion for plugging with a mating connector and a plurality of contact elements supported by the insulating housing and is so compact that the contact elements are arranged very closely. Consequently, crosstalk or noise is produced between adjacent contact elements especially between elongated straight portions of the contact elements. 
     Japanese patent application Kokai Nos. 7-106010 and 8-64288 have proposed improvements in reduction of the crosstalk. 
     The proposed improvements do not need any additional components such as a ground plate or capacitor for reducing the crosstalk and are relatively simple and inexpensive. However, they have the following disadvantages. 
     These conventional modular connectors optimize the crosstalk characteristics by adjusting the overlap of only the intermediate sections of the contact elements. The intermediate sections have a substantially constant dimension for all of the modular connector. When the dimensions of the modular connector are changed, it is impossible to adapt for the change by adjusting the overlap of only the intermediate sections. Thus, there is little freedom in design for optimizing the crosstalk characteristics. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the invention to provide a modular connector having a high degree of freedom in design for optimizing the crosstalk characteristics. 
     According to the invention there is provided a modular connector which comprises an insulating housing having a plugging portion for plugging with a mating connector; a plurality of contact elements supported by the insulating housing; the contact elements each having a contact section arranged within the insulating housing, an intermediate section fixed in the insulating housing, and a connection section extending from the intermediate section; a pair of the contact elements on opposite ends intersecting each other in the intermediate sections; and other pairs of the contact elements arranged such that a distance between them is decreased in the intermediate sections and increased in the connection sections. 
     According to one embodiment of the invention, one of the pairs of the contact elements is made from a first reed frame, and the other from a second reed frame, with one of the first and second reed frames being substantially flat. 
     According to another embodiment of the invention, the intermediate sections are molded with the insulating housing, with the connection sections bent in an L-shape from the insulating housing. 
     According to still another embodiment of the invention, the connection sections of the other pairs of the contact elements spread behind the L-shaped bends. 
     According to yet another embodiment of the invention, the connection sections of the contact elements permit mounting up to the L-shape bends. 
     According to another embodiment of the invention, the insulating housing has the plugging portions at two tiers or more, the contact elements being provided in each of the tiers, and the connection sections of the other pairs of the contact elements are spaced in each of the tiers so as to optimize crosstalk characteristics. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of part of a modular jack type connector according to an embodiment of the invention; 
     FIG. 2 is a sectional view of the modular jack type connector of FIG. 1; 
     FIG. 3 is a top plan view of the lower modular jack type connector of the modular jack type connector of FIG. 1; 
     FIG. 4 is a side elevational view of the modular connector of FIG. 3; 
     FIG. 5 is a bottom plan view of the modular connector of FIG. 3; 
     FIG. 6 is a rear elevational view of the modular connector of FIG. 4; 
     FIG. 7 is a sectional view taken along line  7 — 7  of FIG. 3; 
     FIG. 8 is a sectional view taken along line  8 — 8  of FIG. 5; 
     FIG. 9 is a perspective view of only the contact elements for the modular connector of FIG. 3; 
     FIG. 10 is a top plan view of part of an upper reed frame to provide part of the contact elements for the modular connector of FIG. 3; 
     FIG. 11 is a side elevational view of the upper reed frame of FIG. 10; 
     FIG. 12 is a top plan view of part of a lower reed frame to provide the rest of the contact elements for the modular connector of FIG. 3; 
     FIG. 13 is a side elevational view of the lower reed frame of FIG. 12; 
     FIG. 14 is a bottom plan view of the upper modular connector for the modular jack connector of FIG. 1; 
     FIG. 15 is a side elevational view of the modular connector of FIG. 14; 
     FIG. 16 is a rear elevational view of the modular connector of FIG. 14; 
     FIG. 17 is a bottom plan view of part of an upper reed frame to provide part of the contact elements for the modular connector of FIG. 14; 
     FIG. 18 is a side elevational view of the upper reed frame of FIG. 17; 
     FIG. 19 is a bottom plan view of part of a lower reed frame to provide the rest of the contact elements for the modular connector of FIG. 14; and 
     FIG. 20 is a side elevational view of the lower reed frame of FIG.  19 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the invention will now be described with reference to the accompanying drawings. 
     FIG. 1 is a front elevational view of part of a modular jack type connector according to an embodiment of the invention, and FIG. 2 is a sectional view of the connector. An insulating housing  100  is covered by a shield plate and has upper and lower jack openings  120  and  110 . Only one jack opening is shown for each of the upper and lower tiers. These jack openings  110  and  120  are constructed so as to receive modular plug type connectors  10  as shown in FIG.  2 . The modular plug type connectors  10  are well known and will not be described in detail. A plurality of groups of contact elements  200  and  300  are provided in the jack openings  110  and  120 , respectively. In order to provide high-speed transmission, there is provided a differential transmission system wherein a pair of data pulse signal and its inverted signal are transmitted simultaneously. Each of the contact groups  200  and  300  consists of eight contact elements in this embodiment. 
     The structure of the modular connector in each tier will be described in detail with respect to FIGS. 3-20. 
     The modular connector in the lower tier will be described with respect to FIGS. 3-13. FIG. 3 is a top plan view of the modular connector, FIG. 4 is a side elevational view thereof, FIG. 5 is a bottom plan view thereof, FIG. 6 is a rear elevational view thereof, FIG. 7 is a sectional view taken along line  7 — 7  of FIG. 3, and FIG. 8 is a sectional view taken along line  8 — 8  of FIG.  5 . As shown in these figures, the lower modular connector comprises an insulating housing  101  and a group of contact elements  200  provided in the insulating housing  101 . The contact element group  200  consists of eight contact elements  201 - 208  each having a contact section  201 A- 208 A, an intermediate section  201 B- 208 B, and a connection sections  201 C- 208 C. 
     FIG. 9 shows only the contact element group  200  arranged in the insulting housing  101  for easy understanding. The contact elements  201  and  202 , and  207  and  208  make pairs 1 and 4, respectively, and are twisted to intersect each other in the intermediate section. The other contact elements  203  and  206 , and  204  and  205  make pairs 2 and 3, respectively, and are bent such that the distance between them is reduced in the intermediate section and increased again at the connection section to minimize the crosstalk or noise. 
     The manufacture of the lower modular connector will be described with reference to FIGS. 10-13. FIG. 10 is a top plan view of an upper reed frame to provide the contact elements  202 ,  204 ,  206 , and  208  and FIG. 11 is a side elevational view thereof. The upper reed frame  210  is made by stamping a resilient conductive metal sheet so as to provide elongated members for the contact elements  202 ,  204 ,  206 , and  208  between the frame sections  211  having take-up holes  212 . As best shown in FIG. 11, the upper reed frame  210  is substantially flat as a whole. 
     Similarly, FIG. 12 is a top plan view of a lower reed frame to provide the contact elements  201 ,  203 ,  305 , and  207  and FIG. 13 is a side elevational view thereof. The lower reed frame  220  is made by stamping and bending a resilient conductive metal sheet so as to provide the contact elements  201 ,  203 ,  205 , and  207  between the frame sections  221  having take-up holes  222 . As best shown in FIG. 13, the lower reed frame  220  is provided with bends  223  and  224  at a position corresponding to the intermediate section of the contact elements and at a position between the frame section  221  and the contact sections of the contact elements, respectively. 
     As shown by phantom line in FIGS. 10 and 12, the insulating housing  101  is molded with the intermediate sections of the contact elements after the upper and lower reed frames  210  and  220  are placed one upon another such that the contact sections of the contact elements are offset by a pitch. Then, the elongated portions corresponding to the contact elements are cut from the frame sections  211  and  221 . Then, as best shown in FIGS. 4 and 9, the contact sections  201 A- 208 A and the connection sections  201 C- 208 C of the contact elements are bent downwardly from the insulating housing  101 . 
     The structure of the upper modular connector will be described with reference to FIGS. 14-20. FIG. 14 is a bottom plan view of the modular connector, FIG. 15 a side elevational view thereof, and FIG. 16 is a rear elevational view thereof. As shown in these figures, the upper modular connector comprises an insulating housing  102  and a contact element group  300  supported by the housing  102 . The contact element group  300  consists of eight contact elements  301 - 308 . The contact elements  301 - 308  each have a contact section  301 A- 308 A, an intermediate section  301 B- 308 B, and a connection section  301 C- 308 C. 
     The contact elements  301  and  302 , and  307  and  308  make pairs 1 and 4, respectively, and are twisted to intersect each other in the intermediate section. The contact elements  303  and  306 , and  304  and  305  make pairs 2 and 3 and are bent such that the distance between them is decreased in the middle portion and increased in the end portion. In this way, according to the invention, the distance between the contact elements is controlled not only in the intermediate section but also over the entire length, thus minimizing the crosstalk or noise. 
     A method of making the upper modular connector will be described with reference to FIGS. 17-20. FIG. 17 is a bottom plan view an upper reed frame  310  for providing the contact elements  301 ,  303 ,  305 , and  307 , and FIG. 18 is a side elevational view thereof. The upper reed frame  310  is made by stamping a resilient conductive metal sheet so as to provide elongated members for the contact elements  301 ,  303 ,  305 , and  307  between the frame sections  311  having take-up holes  312 . As best shown in FIG. 18, the upper reed frame  310  has bends  313  at a position corresponding to the intermediate sections of the contact elements and  314  at a position between the frame section  311  and the connection sections of the contact elements. 
     Similarly, FIG. 19 is a bottom plan view of a lower reed frame  320  for providing the contact elements  302 ,  304 ,  306 , and  308  and FIG. 20 is a side elevational view thereof. The lower reed frame  320  is made by stamping a resilient conductive metal sheet so as to provide elongated members for the contact elements  302 ,  304 ,  306 , and  308  between supporting sections  321  having feeding holes  322 . As best shown in FIG. 20, the lower reed frame  320  is flat as a whole. 
     The upper and lower reed frames  310  and  320  are placed one upon another such that the contact sections of the contact elements are offset by a pitch and then, as shown in FIGS. 17 and 19, the insulating housing  102  is molded in the intermediate sections of the contact elements. Then, the elongated members are cut off from the frame sections  311  and  321 . AE best shown in FIG. 15, the contact sections  301 A- 308 A are bent upwardly from the insulating housing  102  while the connection sections  301 C- 308 C are bent downwardly from the insulating housing  102 . 
     How the contact groups  200  and  300  arranged according to the invention work to reduce the crosstalk or noise will be described with respect to FIG.  3 . Only the crosstalk between the pairs of the contact elements  201  and  202 , and  203  and  206  will be described. For example, even if a negative crosstalk component is induced in the contact section  203 A of the contact element  203  by the contact section  202 A of the contact element  202  which is spaced by a pitch from the contact section  203 A, a small positive crosstalk component is induced in the contact section  203 A by the contact section  201 A spaced two pitches from the contact section  203 A. A negative and a small positive crosstalk components are induced in the front portion of the intermediate section  203 B by the front portion of the intermediate section  202 B spaced by a pitch and the front portion of the intermediate section  201 B spaced by two pitches, respectively. A positive and a small negative crosstalk components are induced in the rear portion of the intermediate sections  203 B by the intermediate sections  201 B spaced by a pitch and by the intermediate sections  202 B spaced by three pitches, respectively. In addition, a positive crosstalk component is induced in the L-shape of the contact sections  203 C by the L-shaped connection sections  201 C spaced by a pitch. The lengths of the respective sections and the distance between the contact elements are determined such that the sum of the crosstalk components is zero. The other contact elements are made in the same way. 
     The modular connector according to the invention not only improve the crosstalk but also reduces the height of the modular connector mounted on a board. As shown by phantom line in FIGS. 6 and 16, the mounting surface of the board  1  can be brought into the L-shaped sections. 
     Since the crosstalk is improved by not only the intermediate sections but also the connection sections, there is more freedom in design. It is easy to optimize the crosstalk characteristics of a connector of each tier by controlling the spread of the L-shaped connection sections of the respective contact elements. The contact elements are mounted on a board up to the L-shaped sections so that the height of the connector is minimized. Since the L-shaped sections are made outside the insulating housing, the upper and lower moldings are interchangeable for the two-tier receptacle. Since two kinds of reed frames are placed one upon another and the insulating housing is molded at the intermediate sections of the contact elements, it is easy to make the connector. One of the reed frames is made so flat that the integral molding is very easy.