JPH0684568A - Electric connector - Google Patents

Abstract

PURPOSE: To minimize the change in characteristics over the entire length of a signal contact of a high-frequency signal transmission electrical connector. CONSTITUTION: Insulating housings 12 and 14 are provided with dielectric partitions 32 and 34 having a definite thickness, a central slot 30, and contact cavities 20 and 22. An earthing path 90 is inserted and retained in the central slot 30, and two lines of signal contacts 70 and 80 are inserted and retained in the contact cavities 20 and 22. The earthing path 90 has upper and lower earthing paths back to back, and elastic protrusions 108 and 110 are formed in the lower earthing path, and elastic protrusions 128 and 130 are formed in the upper earthing path. The earthing path 90 pressed against the partitions 32 and 34 is retained. On the other hard, the signal contacts 70 and 80 are pressed against the other faces of the partitions 32 and 34. This substantially realizes an electrical connector 2 having a microstrip structure which exhibits an almost constant characteristic impedance.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrical connectors, and more particularly to a right angle interconnection between, for example, two circuit boards or between a circuit board and an orthogonal conductor array such as a flat transmission cable. The present invention relates to an electrical connector assembly employed for making impedance-matched electrical connection of interconnected signal lines of an electrical connector intended to achieve. [0002] US Patent Nos. 4,762,500 and 4,747,7
No. 87 discloses an impedance-matched electrical connector for interconnecting a plurality of circuits such as a pair of printed circuit boards or a transmission cable and a printed circuit board. These connectors have a central ground path (bus bar) and a plurality of receptacle-type signal terminals arranged in parallel on both sides thereof. Both the receptacle terminal and the ground path of the mating connector halves are fully matable, maintaining the same impedance between the connectors. Since each connector generally employs the microstrip transmission principle to establish interconnections, it minimizes impedance variations between the input components, whether cables or printed circuit boards, and the output components, which are also cables or printed circuit boards. U.S. Pat. Nos. 4,695,106 and 4,762,500 particularly disclose electrical connectors for electrically connecting a large number of signal lines on two orthogonally arranged printed circuit boards. Achieving the required impedance levels in the manufacturable products used for the components shown in these patents has proven difficult. Hereinafter, this will be described in detail. It has been found that connectors designed with established dimensional relationships for use with microstrip printed circuit boards cannot be acceptable performance microstrip connectors. The reason is that, unlike microstrip circuit boards, electrical connectors do not have signal or ground conductors in close contact with the surrounding dielectric material. The air gap between metal and plastic (dielectric) is created to accommodate manufacturing tolerances or differences in coefficient of thermal expansion, which is due to the dielectric constant of the housing material being higher than the air above the PCB trace and the substrate below that trace. Also has a big impact. In addition, there is dielectric material on the signal contacts of the connector, but there is no dielectric at that location on the microstrip printed board. In part, these differences show some inconsistencies in conventional microstrip formulas when applied directly to electrical connectors that employ the microstrip principle. Therefore, the present invention provides an electrical connector which eliminates the instability or variation of the characteristic impedance that accompanies the conventional impedance matching type electrical connector and can obtain a desired characteristic impedance. The purpose is to do. SUMMARY OF THE INVENTION The electrical connector of the present invention is an electrical connector having at least one row of signal contacts separated from the ground path by a dielectric bulkhead, both of which have a signal contact and a ground path. It has means for pressing against the separating dielectric partition to reduce impedance changes along the signal contact. According to the present invention, the inner peripheral surface of the receptacle-type signal terminal is brought closer to the outer peripheral surface of the receptacle-type ground path than the distance between the adjacent surfaces of the signal terminals. It has been found that the desired characteristic impedance can be obtained if the spacing between and is kept substantially constant over at least a length greater than the wavelength of the transmitted signal. The preferred embodiment of the present invention comprises a practical and manufacturable electrical connector assembly. This electrical connector assembly can be used for interconnection between circuits having a characteristic impedance of 50 Ω, the connector described herein is substantially transparent to signals, and is almost transparent to signals transmitted through the connector. Has no effect.
In particular, the electrical connector embodying the present invention has means for maintaining the positional relationship between the signal terminal parallel ground paths even at right angles without causing a significant difference in impedance of the signals transmitted therethrough. Transmission of relatively high speed signals between two orthogonal signal line arrays, such as two orthogonally arranged printed circuit boards or a flat transmission cable extending at right angles to the printed circuit boards, is accomplished by using a microstrip transmission line. Achieved by an electrical connector having a morphology. A signal can be transmitted in this manner when one or more rows of signal contacts are arranged near the ground path. To interconnect orthogonally arranged signal arrays, both the signal contacts and the midpoints between the ground paths are bent at right angles together. The signal contact is located in the cavity of the insulating housing and the ground path is located in the slot near the row of cavities. In order to maintain the gap required for microstrip signal transmission between the signal contact and the ground path, they are pressed against each other. The signal contacts are pressed towards the ground path, for example using elastic tabs that engage the housing. The ground path is formed of two components, one ground path component engaging the other component and urged toward an adjacent signal contact. If the ground paths are located at the midpoints between the two rows of signal contacts, each ground path employs a protrusion that engages a corresponding protrusion on the other ground path component, thereby allowing the two ground path components to Each may be pressed toward the signal contact closest to its ground path component. In the electrical connector of the microstrip signal transmission structure, the signal contact and the ground path are separated by the internal dielectric partition. By pressing both the signal contact and the ground path against this dielectric bulkhead over substantially the entire length of the signal contact, the change in impedance along the length of the signal contact is reduced, resulting in distortion of the high-speed signal transmitted through the connector. Will never occur. Preferred embodiments of the electrical connector according to the present invention will be described in detail below with reference to the accompanying drawings. The electrical connector 2 according to the preferred embodiment of the present invention is used to interconnect two conductor arrays, such as two printed circuit boards, which use a microstrip structure that matches the impedance of each signal line of the conductor array very well. It is possible. The electrical connector 2 is intended especially for making right-angled interconnections.
The receptacle connector 2 can be fitted with a mating connector such as a pin header 4 fixed to another printed circuit board. The electrical connector 2 is composed of an insulating housing 10 including a plurality of signal terminals 70 and 80. These signal terminals 7
0 and 80 are arranged in two rows in the cavities 20 and 21 of the insulating housing 10 in the preferred embodiment. The receptacle-type connector 2 also includes a ground path 90, which is located between two rows of signal contacts in a slot 30 formed between the cavities 20 and 22. The insulating housing 10 comprises an upper housing member 12 and a lower housing member 14. The upper housing member 12 includes a plurality of contact cavities 20, 22 arranged in two rows on either side of the ground pass slot 30. As shown in FIGS. 4 and 5, the lower housing member 1
4 is mounted at a right angle to the upper housing member 12 and includes a plurality of outer cavity extensions 24a, 24b and inner cavity extensions 26a, 26b. The cavity extensions 24a and 24b are the upper housing cavity 20.
And communicates at a right angle with the upper housing member 12. Figure 4,
As shown in FIGS. 5 and 15, lower housing cavity extensions 24a, 24b outside the lower housing member 14 are shown.
Are staggered (staggered), and each cavity 24a is connected to the ground path 90 more than the adjacent outer cavity extension 24b.
Get closer to. The internal cavity extensions 26a and 26b communicating with the lower cavity 22 are also staggered. Lower housing cavity extensions 24a, 24b,
By making 26a and 26b staggered, the signal contact can be made staggered. Therefore, the center line interval on the printed circuit board on which the receptacle-type connector 2 is fitted is widened, and the signal contacts 70 and 80 are fitted in the lateral direction. Space can be constant. In the preferred embodiment of the present invention shown in FIGS. 1 to 3, the signal contacts of the connector fitting base 16 of the receptacle-type connector 2 are arranged at a center interval of about 1.3 mm2. At the board-engaging surface 18 of the receptacle-type connector 2, the signal contacts are staggered about 2.5 mm apart, which is compatible with conventional printed circuit board construction. As shown in FIG. 13, the two housing members 12 and 14 are connected by abutting portions 38 and 40, and the upper housing member on the minus side of the cavities 20 and 22 and the abutting portions 38 and 40 is a cavity extension portion. 24a, 24b, 26a, 26
b and the lower housing member 1 on the other side of the contact portions 38, 40
It extends at a right angle to 4. Each of the cavities 20, 22 and the upper housing member 12 includes an inner housing slot wall 3
2, 34 separate from a central slot 30 extending between the two rows of cavities. Adjacent cavities 2 in each row
0 and 22 are separated by a wall 36 that extends perpendicular to the inner slot walls 32 and 34. As shown in FIG. 15, each of the cavity extension portions 24 a and 24 b located outside the slot 30 of the lower housing member 14 includes the lower housing member 1.
4 consists of a hole extending through the body. As shown in FIG. 1, the cavity extending portions 26 a and 26 b of the insulating housing 10 extending between the board fitting surface 18 and the contact portion 40 of the lower housing member 14 are engaged with each other by the upper housing member 12 and the lower housing member 14. It is defined by The plurality of signal lead supporting recesses 42 shown in FIG. 15 are formed after the upper housing member 12. A mating signal lead support tongue 44 is formed on the outer surface of the lower housing member 14. The tongues 42 are fixed in the recess 42 when the lower housing member 14 is attached to the upper housing member 12 to form the insulating housing 10. The signal lead opening 48 forms a channel, and the signal contacts 70 and 8 are formed.
Receive 0 lead. Engagement of the tongue 44 with the signal lead support recess 42 allows the lead to be inserted into the cavity extension 26b located closest to the ground path 90. Also, the ridge 50 on the upper housing member 12
Includes signal lead opening channel 48 and cooperates with lower housing member 14 to provide signal contact lead 26a.
Are inserted in the outermost rows of the lower side of the housing 10.
By fitting the upper housing member 12 and the lower housing member 14, the lead portion of the signal contact 80 is connected to the ground path 9
The position below 0 is clearly shown in the bottom view of the connector 2 shown in FIG. As shown in FIGS. 6 and 14, the receptacle-type connector 2 is fixed to the printed circuit board 6 by the board mounting extensions 54 at the respective ends of the upper housing member 12. Further, these board attachment extensions 54 constitute means for engaging and holding the lower housing member 14 with the upper housing member 12. The board mounting extension 54 is deflectable outwardly so that the lower housing member 14 can be snap-engaged with the upper housing member 12. As shown in FIG. 14, each board mounting extension 54 has a resilient arm 60 from which a pedestal 56 extends. In the preferred embodiment of the invention, pedestal 56 includes a hole 58 suitable for receiving a post, such as a screw 64 (see FIG. 1). The screw 64 passes through the hole 58 and the pedestal 56 and constitutes a part of the board mounting means. It will also be appreciated that the integral extension can be formed on a board mounting means suitable for interference fit with the hole in the printed board 6. The inwardly extending flange 62 of the resilient arm 60 provides a means for securing the lower housing member 14 to the upper housing member 12. An outwardly extending rib 66 is provided on the lower housing member 14, which cooperates with the flange 62 to secure the lower housing member 14 to the upper housing member 12. When the lower housing member 14 is moved upward to engage the upper housing member 12, the resilient arm 60 cams outward with the ribs 66 engaging the flanges. Once the rib 66 has passed the flange 62, the resilient arm 60 snaps back to retain the lower housing member 14 in the upper housing member 12. Upper housing member 12 and lower housing 1
Correct alignment between the four is maintained by mating pins 52 extending upwardly from the lower housing member 14. As shown in FIGS. 4 and 5, the signal contact 70 is disposed inside the insulating housing 10, and the ground path 90 is disposed at the center of the outside thereof. In addition, the terminal signal contact 80 is arranged inside or under the insulating housing 10 near the ground path 90. The signal terminal 70 includes the lower housing cavity extensions 24a and 24b and the cavity 2.
It is placed in 0. Similarly, the signal contact 80 includes the cavity 22 and the lower housing inner cavity extension 26.
a, 26b. Signal contact 70, 80
Each has a right-angled bend located near the joint or abutment 38, 40 of the upper housing member 12 and the lower housing member 14. The signal contacts 70, 80 extend between the abutting portions 38, 40 and the mating surface 16 and have contact mating portions 72, 82 arranged on the upper housing member 12. Further, the signal contacts 70 and 80 extend at right angles to the contact fitting portions 72 and 82 and extend into the lower housing member 14 between the contact portions 38 and 40 of the receptacle-type connector 2 and the board mounting surface 18. 7
4, 84. The adjacent signal contact leads in each row are staggered (staggered) in the same pattern as the stagger structure of the cavity of the fitting housing. Each signal contact 7
0 and 80 have tabs 76 and 86, which have means for pushing the signal contacts 70 and 80 inwardly toward the ground path 90. The tabs 76 and 86 are contact fitting portions 7
The signal contacts 70 and 80 near the fitting portions 72 and 82 are pressed inward toward the grounding path 90 and against the slot walls 32 and 34 near the fitting portions 72 and 82, and the entire length of the signal contacts. Reduce the change in impedance over. The tabs 76, 86 engage the sides of the corresponding cavities 20, 22 located opposite the inner slot walls 32, 34 between the cavities 20, 22 and the slot 30.
Also, the tabs 76, 86 retain the signal pins in the housing until assembly is complete. Note that the upper signal contact 70 is pressed downward as shown in FIG. 4 and is pressed upward toward the lower signal contact 80 ground path 90. Further, the signal contacts 70 and 80 have right-angled bent portions 78 and 88 between both ends. Since the adjacent signal contacts are staggered as shown in FIGS. 4 and 5, the position of the right-angled bent portion with respect to the fitting portion is different between the long and short signal contacts. The ground path 90 disposed in the slot 30 also has a right-angled bent portion, and the upper housing member 12
And a joining or abutting portion 38 between the lower housing member 14 and
It is arranged along 4〓. The ground path 90 is disposed in the central portion of the receptacle-type connector housing 10 as shown in FIG.
6, the lower path portion 100 shown in FIGS. 17 and 18,
The upper path portion 120 shown in FIGS. 19 to 21 is fitted to form a single ground path. Each ground path 90 includes blade portions 112, 132, each blade portion being disposed within the upper housing member 12. It includes a pass fitting portion 92 and a pass lead portion 94 having leads 114 and 134. Each path portion 100, 120 includes a right-angled bent portion in the middle of its both ends. The leads 114 and 134 extend downward from the ends of the blade portions 112 and 132 to the pass lead portions 94 of the respective pass portions 100 and 120. The path fitting portion 92 includes inwardly bent portions 102 and 122 of elastic metal contacts. The contact portions 104 and 124 face each other, and the path fitting springs 102 and 122 have flexibility outward with respect to the center line of the slot 30. Separation fingers 116 and 136 are formed at each path fitting portion. Each path fitting portion 92 extends from inwardly extending bent portions 106 and 126, and a part of the path fitting portion between the bending portion 106 and the inward bending spring 102 abuts on the slot wall surfaces 32 and 34. It is normal. A plurality of protrusions 108, 110, 128, and 130 are punched out from the surface of the blade-shaped portion, and the ground path portions 100 and 120 are connected to the slot wall surface
2, 34 are pressed into contact with each other. Each protrusion engages the other path portion so that both ground path portions are in close contact with one of the rows of signal contacts 70, 80 to reduce impedance changes along the entire length of the signal contacts 70, 80. Protrusion 10
8, 110, 128 and 130 are blade portions 112, 132
Located inside. The protrusions 108 and 128 are arranged in the path fitting portion 92, while the protrusions 110 and 130 are arranged in the path lead portion. As shown in FIGS. 16, 17, 19 and 20, two protrusions are formed along the width direction of the ground path. Also, two protrusions are formed along the length direction of the ground path. The protrusions 108 and 110 are bent at right angles 118.
Protrusions 128 and 130 formed on both sides of the
It is formed on both sides of 38. Therefore, each ground path 100,
Reference numeral 120 has at least one protrusion protruding from the path fitting portion and at least one protrusion protruding from the path lead portion. The protrusions 108, 110, 128 and 130 push the ground path portions 100 and 120 outwardly to engage the slot wall surfaces 32 and 34, while the tabs 76 and 86 similarly push the signal contacts 70 and 80 to the slot wall surface 32. , 34
Since it presses so as to engage with the signal contact 70,
The gap between 80 and ground path 90 remains constant. An alternate embodiment of the ground path shown in FIGS. 24-30 comprises two sections 100 'and 120'. In this embodiment, the protrusions 108 ', 110', 12
8'and 130 'are curved surfaces. As shown in FIGS. 24 to 30, the protrusions 108 ′ and 110 ′ project in the direction perpendicular to the longitudinal direction of the lead 114 and are fitted into the protrusion 12 of the path half body.
It extends at right angles to 8'and 130 '. Since the other elements of this modified embodiment are the same as the corresponding elements of FIGS. 16 to 21, the same reference numerals are attached with “′” to show the corresponding relationships. In this way, the relationship between each row of signal contacts and the centrally located ground path is similar to the relationship between the conventional microstrip line signal and ground conductors, and the signal contacts are parallel to the ground path. Also note that they are spaced at regular intervals. The blades 112, 132 are pressed outwardly to engage the insulating material between the signal contact and the ground path. This is true over most of the entire length between the front mating surface 18 and the board mating surface 16. It is apparent that the elastic fitting springs 102 and 122 of the path fitting portion tend to separate from the slot wall surfaces 32 and 34 when the connector is not fitted. However, comparing FIG. 4 to FIG. 5 with FIG. 6 to FIG. 7, when the receptacle-type connector 2 is fitted with the fitting connector 4 including the substantially flat plate-shaped grounding member 140, the fitting springs 102 and 122 are moved outward. Bending and grounding path parts 100, 1
It is shown that the spacing of this portion of 20 will be similar to the spacing of the rest of the blades 112, 132. 8 to 12 are cross-sectional views of different parts along the mated connector, showing that a large part of the entire length of the signal contacts 70 and 80 has a substantially microstrip line structure. Opposing protrusions 108, 12 of the pass portions 100, 120
The eight engagement is clearly shown in FIG. The pressing force in the normal direction can be improved by applying a load to the ground path fingers in advance. The pin locator 19 is shown in FIG. This pin locator 19 includes a signal contact leg and a ground path leg 11
The through holes 4,134 are pre-aligned with the holes of the printed circuit board to which the connector 2 is attached (play alignment). A semi-circular preform can be placed on the filmstrip forming this pin locator. The semicircular preform or donut is then heated and reflowed. The filmstrip 19 shifts up the leads,
The bottom surface of the slot 30 is covered to prevent dust and the like from adhering thereto. Although the preferred embodiment of the present invention is an electrical connector between the boards, it can also be used for electrical connection between the printed circuit board 6 and the flat cable connector. Also, means for maintaining the microstrip line structure by pushing the ground path outward to engage the slot wall surface and the signal contacts inward to engage the same dielectric wall surface is a receptacle type Connector 2
It is needless to say that the present invention can be applied not only to the right-angled connector as described above but also to a straight type vertical connector composed of two parallel signal conductor arrays. As described above, various modifications can be made without departing from the gist of the present invention. As is apparent from the above description, according to the electrical connector of the present invention, a large number of signal contacts and ground paths are pressed against each other on both sides of a dielectric partition having a uniform thickness. It has a pressing means. As a result, the distance between the signal contact and the ground path is kept constant over the entire length of the signal contact, so that a microstrip line structure having a characteristic impedance determined by the material and thickness of the conductor and the partition is realized. Therefore, it is possible to obtain a high-performance high-frequency high-speed signal transmission electrical connector that minimizes signal distortion caused by reflection or the like in a signal transmitted through a signal contact without being affected by assembly accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a right angle receptacle type connector showing a fitting surface of an embodiment of an electrical connector of the present invention. FIG. 2 is a bottom view of the electric connector of FIG. 3 is a side view of the electrical connector of FIG. 4 is a cross-sectional view taken along the line 4-4 in FIG. 5 is a cross-sectional view taken along the line 5-5 in FIG. 6 and 7 are assembled sectional views of the electric connector of FIG. 1 fitted with a pin header. 8 to 12 are lines 8-8 of FIGS. 6 and 7, respectively.
Sectional drawing which follows 9-9, 10-10, 11-11, and 12-12. 13 is a cross-sectional view of upper and lower insulating housings of the electrical connector of FIG. 14 is a front view of the insulating housing of FIG. FIG. 15 is a bottom view of the insulating housing of FIG. 16-18 are top, back and side views, respectively, of the lower half of the ground path. 19-21 are top, back, and side views, respectively, of the upper half of the ground path. 22 is a side view of the upper signal contact used in the electrical connector of FIG. 1. FIG. 23 is a side view of the lower signal contact used in the electrical connector of FIG. 24 to 26 are top, back and side views, respectively, of the lower half of another embodiment of a right angle ground path. 27-29 are top, back and side views, respectively, of the upper half of another embodiment of a right angle ground path. FIG. 30 is a cross-sectional view of the ground path shown in FIGS. 24 to 29. [Description of Reference Signs] 2 electrical connector 32, 34 dielectric partition wall 90 ground path 70, 80 signal contact 108, 110, 128, 130 pressing means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Paul Peter Swinwinski             33542, Florida, United States             Minor 101st Avenue North             12108 (72) Inventor Robert A. Smith             United States Florida 34641 LA             Gogo APT. 513 Ulmerton               Road 7350 (72) Inventor Richard E. Thurman             33542, Florida, United States             Minor 117th Street North             11109

Claims (1)

Claims: At least one separated from a ground path by a dielectric barrier.
An electrical connector having a row of signal contacts, comprising means for pressing the signal contacts and the ground path toward the dielectric partition to reduce impedance changes along the signal contacts.