Patent Application
20050208823
1. Field of the Invention
The present invention relates generally to cable connectors for differential transmission, and more particularly to a cable connector for differential transmission employed to transmit a high-speed signal.
2. Description of the Related Art
There are two types of data transmission methods: a normal transmission method and a differential transmission method. The normal transmission method employs an electric wire for each data item. The differential transmission method, using a pair of electric wires for each data item, simultaneously transmits a “+” signal to be transmitted and a “−” signal equal in magnitude and opposite in direction to the “+” signal. The differential transmission method, which has the advantage of being less susceptible to noise compared with the normal transmission method, has been used more widely. A cable connector for differential transmission (a differential transmission cable connector) has a plug provided to an end of a differential transmission cable and covered by a shield cover. The differential transmission cable connector is applied to the differential transmission method, and is used, for instance, to connect a computer and a server.
The first and second signal wires 23-1 and 23-2 form a pair line.
Referring to
Japanese Laid-Open Patent Application No. 2003-059593 discloses a conventional cable connector for differential transmission.
Focusing on the shield between adjacent data transmission channels, the differential transmission cable connector 10 has a problem in the part of the relay board 12. On both the upper and lower surfaces of the relay board 12, wiring patterns extending along the Y-axis are formed side by side along the X-axis. The vertically aligned upper and lower wiring patterns form a wiring pattern pair so that the wiring pattern pairs are formed side by side along the X-axis on the relay board 12. Accordingly, for structural reasons, it is difficult to provide as good a shield between each two adjacent wiring pattern pairs as in the contact assembly 11.
In these years, signals processed by computers and servers have become higher in speed, so that adverse effects on transmission characteristics due to low shielding provided by the relay board 12 have become unignorable.
Further, in terms of production costs, it is required that differential transmission cable connectors be structured so that they can be assembled with efficiency with good productivity.
Accordingly, it is a general object of the present invention to provide a differential transmission cable connector in which the above-described disadvantages are eliminated.
A more specific object of the present invention is to provide a differential transmission cable connector improved in high-speed signal transmission characteristics.
The above objects of the present invention are achieved by a cable connector for differential transmission, including: a contact assembly including an electrically insulating block body in which signal contact pairs and ground contacts are incorporated to be arranged side by side alternately, the signal contact pairs each being formed of first and second signal contacts, the first signal contact having a first signal wire connection part thereof projecting from a surface of the block body, the second signal contact having a second signal wire connection part thereof projecting from the surface of the block body, the ground contacts each having a drain wire connection part thereof projecting from the surface of the block body; and an alignment member including a signal wire alignment part and a joining part joined to the contact assembly, the signal wire alignment part being configured to align first signal wires and second signal wires extending from an end of a differential transmission cable so that the first and second signal wires are arranged in positions corresponding to the first and second signal wire connection parts, respectively, wherein the alignment member is joined to the contact assembly through the joining part on a side of the surface of the block body, the differential transmission cable includes a plurality of pair wires each formed of a corresponding one of the first signal wires, a corresponding one of the second signal wires, and a drain wire, the first and second signal wires are connected to the first and second signal wire connection parts, respectively, and the drain wires are connected to the drain wire connection parts.
The above objects of the present invention are also achieved by a cable connector for differential transmission, including: a contact assembly including an electrically insulating block body in which signal contact pairs and ground contacts are incorporated to be arranged side by side alternately, the signal contact pairs each being formed of first and second signal contacts, the first signal contact having a first signal wire connection part thereof projecting from a surface of the block body, the second signal contact having a second signal wire connection part thereof projecting from the surface of the block body, the ground contacts each having a drain wire connection part thereof projecting from the surface of the block body; and an alignment member including a pair wire alignment part and a joining part joined to the contact assembly, the pair wire alignment part being configured to align a plurality of pair wires included in a differential transmission cable in a direction in which the signal contact pairs and the ground contacts are arranged side by side alternately, wherein the alignment member is joined to the contact assembly through the joining part on a side of the surface of the block body, each of the pair wires is formed of a first signal wire, a second signal wire, and a drain wire, the first and second signal wires are connected to the first and second signal wire connection parts, respectively, and the drain wires are connected to the drain wire connection parts.
The above objects of the present invention are also achieved by a cable connector for differential transmission, including: a contact assembly including an electrically insulating block body in which signal contact pairs and ground contacts are incorporated to be arranged side by side alternately, the signal contact pairs each being formed of first and second signal contacts, the first signal contact having a first signal wire connection part thereof projecting from a surface of the block body, the second signal contact having a second signal wire connection part thereof projecting from the surface of the block body, the ground contacts each having a drain wire connection part thereof projecting from the surface of the block body; and an alignment member including a pair wire alignment part, a signal wire alignment part, and a joining part joined to the contact assembly, the pair wire alignment part being configured to align a plurality of pair wires included in a differential transmission cable in a direction in which the signal contact pairs and the ground contacts are arranged side by side alternately, the pair wires each being formed of a first signal wire, a second signal wire, and a drain wire, the signal wire alignment part being configured to align the first and second signal wires extending from an end of the differential transmission cable so that the first and second signal wires are arranged in positions corresponding to the first and second signal wire connection parts, respectively, wherein the alignment member is joined to the contact assembly through the joining part on a side of the surface of the block body, the first and second signal wires are connected to the first and second signal wire connection parts, respectively, and the drain wires are connected to the drain wire connection parts.
According to the present invention, the first and second signal wires and the drain wires of the differential transmission cable are directly connected to the first and second signal contacts and the ground contacts, respectively, of the contact assembly. Further, the rear ends of the ground contacts extend further in the rear direction than those of the first and second signal contacts.
Accordingly, a better shield is provided between a differential signal transmission channel and another differential signal transmission channel adjacent thereto, thus resulting in better transmission characteristics. Therefore, the above-described differential transmission cable connectors are employable for a high-speed signal transmission channel.
Further, the alignment member, aligning the pair wires and the first and second signal wires to the contact assembly, is joined to the contact assembly, thereby forming a differential transmission cable connector temporary assembly. Since electric welding is performed with respect to the temporary assembly, the welding of the first and second signal wires to the first and second signal contacts and the welding of the drain wires to the ground contacts can be performed with good operability.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:
A description is given below, with reference to the accompanying drawings, of an embodiment of the present invention.
Schematically, the differential transmission cable connector 50 has a structure formed by removing the relay board 12 from the differential transmission cable connector 10 shown in
Next, a description is given of the contact assembly 60 included in the differential transmission cable connector 50.
Referring to
A Z1-side end surface part 80b1 of the projecting shield part 80b is connected to the corresponding drain wire 85. Further, the projecting shield part 80b has hook parts 80c and a cutout part 80d formed therein on the side of its end P1. The hook parts 80c are provided for a jig for press-fitting the ground contact 80. A below-described horizontal part 118 (
On the Y1 side of the contact assembly 60, the beam parts 70-1c and the beam parts 70-2c are aligned in two respective rows along the X-axis, and the pairs of the beam parts 70-1c and 70-2c and the projecting shield parts 80b are aligned, arranged alternately along the X-axis.
Next, a description is given of the alignment member 100 included in the differential transmission cable connector 50.
The alignment member 100, which is a synthetic resin molded component, includes a pair wire alignment part 101 on the Y1 side. The pair wire alignment part 101 separates each two adjacent pair wires 21 so that the pair wires 21 are arranged along the X-axis with a predetermined pitch. The alignment member 100 also includes a signal wire alignment part 110 on the Y2 side of the pair wire alignment part 101. The signal wire alignment part 110 aligns the first and second signal wires 23-1 and 23-2 so that the first signal wires 23-1 are separated from the second signal wires 23-2 along the Z-axis. The alignment member 100 also includes a comb teeth part 120 extending from the signal wire alignment part 110 in the Y2 direction. The alignment member 100 further includes the arm parts 130 and 131 extending from the X1 side and X2 side, respectively, of the pair wire alignment part 101 and the signal wire alignment part 110 in the Y2 direction. From a structural point of view, the main body of the alignment member 100 is a rectangular frame body 102 elongated along the X-axis. The pair wire alignment part 101 is provided inside the frame body 102. The arm parts 130 and 131, serving as connecting parts, extend from the X1 side and X2 side, respectively, of the frame body 102. The signal wire alignment part 110 is provided to extend along the X-axis between intermediate portions of the arm parts 130 and 131.
The pair wire alignment part 101 includes tunnels 105 arranged along the X-axis, the tunnels 105 each holding a corresponding one of the pair wires 21. Specifically, U-shaped partition walls 103 and inverse U-shaped partition walls 104, opposing each other along the Z-axis, are arranged along the X-axis so that the elliptic tunnels 105, each elongated along the Z-axis, are formed to be arranged along the X-axis, communicating with one another at their center portions.
The signal wire alignment part 110 includes a Z1-side first signal wire alignment part 111 and a Z2-side second signal wire alignment part 112. The first signal wire alignment part 111 includes U-shaped grooves 113a arranged along the X-axis, the U-shaped grooves 113a each holding a corresponding one of the first signal wires 23-1. The second signal wire alignment part 112 includes U-shaped grooves 114a arranged along the X-axis, the U-shaped grooves 114a each holding a corresponding one of the second signal wires 23-2. Specifically, the first signal wire alignment part 111 includes U-shaped parts 113 arranged at intervals along the X-axis, and the second signal wire alignment part 112 includes U-shaped parts 114 arranged at intervals along the X-axis. The U-shaped parts 113 and 114 include the U-shaped grooves 113a and 114a, respectively. The slit 115 is formed between each two adjacent U-shaped parts 113 and between the corresponding adjacent U-shaped parts 114. The slits 115 receive the corresponding projecting shield parts 80b. Referring to
Referring to
As shown in
The U-shaped parts 113 and 114 project from the horizontal part 118 in the Y2 direction. The horizontal part 118 is shaped like a triangular prism having a vertical angle on the Y1 side. The horizontal part 118 includes slopes 119a and 119b serving as guide parts. When the first and second signal wires 23-1 and 23-2 move in the Y2 direction from the Y1 side, the slope 119a guides the end of each first signal wire 23-1 toward the Z1 direction, or the direction of the corresponding U-shaped groove 113a, and the slope 119b guides the end of each second signal wire 23-2 toward the Z2 direction, or the direction of the corresponding U-shaped groove 114a.
The comb teeth part 120 is a group of teeth 121 each projecting in the Y2 direction from an intermediate position along the Z-axis between the corresponding U-shaped parts 113 and 114. Each tooth 121 is interposed between the corresponding beam parts 70-1c and 70-2c with the alignment member 100 being joined to the contact assembly 60. Thereby, the tooth 121 sets the impedance between the beam parts 70-1c and 70-2c to a predetermined value. Further, when a force is applied to bend the beam parts 70-1c and 70-2c in a direction to reduce the distance therebetween along the Z-axis, the tooth 121 receives the Y2-side portion of each of the intermediate parts 70-1b and 70-2b so as to prevent the beam parts 70-1c and 70-2c from being bent. A slit 122 is formed between each two adjacent teeth 121. The slits 122 are aligned with the corresponding slits 115 and connected thereto along the Y-axis. The slits 122 receive the projecting shield parts 80b.
The arm parts 130 and 131 are formed so that their (Y2) ends are fitted into the recesses 68 and 69, respectively, of the base part 62 of the block body 61 included in the contact assembly 60.
Next, a description is given of the manufacturing process of the differential transmission cable connector 50.
The manufacturing, or assembling, process of the differential transmission cable connector 50 includes (a) an alignment process, (b) a joining process, and (c) a welding process.
(a) Alignment Process
As shown in
In the alignment operation, the first and second signal wires 23-1 and 23-2 of each pair wire 21, whose end has been processed, are inserted into the alignment member 100 from the Y1 side.
The end of each pair wire 21 is slightly pressed into an elliptic shape and inserted into the corresponding tunnel 105. As a result, the pair wire 21 is held and retained inside the tunnel 105.
The first signal wire 23-1 extending from the pair wire 21 is pushed into the corresponding U-shaped groove 113a to be held and retained therein, thus projecting in the Y2 direction. The second signal wire 23-2 is pushed into the corresponding U-shaped groove 114a to be held and retained therein, thus projecting in the Y2 direction. The distance between the first and second signal wires 23-1 and 23-2 along the Z-axis slightly widens toward the Y2 direction.
The drain wire 25 is positioned on the immediate X1 side of the aligned first and second signal wires 23-1 and 23-2, and is bent into an L-letter shape to be projecting in the Y2 direction.
Thus, when one of the pair wires 21 is positioned, the next one of the pair wires 21 is positioned adjacently, so that the pair wires 21 are arranged adjacently to be aligned with one another. When the paired first and second signal wires 23-1 and 23-2 are aligned, the next paired first and second signal wires 23-1 and 23-2 are aligned in an adjacent position, so that the pairs of the aligned first and second signal wires 23-1 and 23-2 are arranged adjacently to be aligned with one another.
Accordingly, the pair wires 21 extending irregularly from the end of the differential transmission cable 20 are arranged to be aligned long the X-axis by the pair wire alignment part 101. Further, the first and second signal wires 23-1 and 23-2 extending from the ends of the pair wires 21 are arranged to be aligned along the Z-axis and the X-axis by the signal wire alignment part 110.
When each pair wire 21 is inserted into the alignment member 100 from the Y1 side, the first and second signal wires 23-1 and 23-2 are guided by the slopes 119a and 119b toward the Z1 and Z2 directions to be positioned close to the U-shaped grooves 113a and 114a, respectively. Accordingly, the operation of pushing the first signal wire 23-1 into the U-shaped groove 113a and the operation of pushing the first signal wire 23-2 into the U-shaped groove 114a are performed with good operability.
(b) Joining Process
As shown in
The projecting shield parts 80b first enter the corresponding slits 122, and then, the corresponding slits 115. Further, each tooth 121 enters the space between the corresponding beam parts 70-1c and 70-2c. The horizontal part 118 is fitted into the cutouts 80d. The arm parts 130 and 131 are fitted into the recesses 68 and 69, respectively, of the block body 61.
Thus, as a result of the fitting of the projecting shield parts 80b into the slits 122 and 115 and the fitting of the arm parts 130 and 131 into the recesses 68 and 69, the alignment member 100 is positioned with respect to the contact assembly 60 and joined thereto.
As shown in
The position of the end portion 70-1e of each beam part 70-1c is controlled by the corresponding beam support part 116, and the end portion 70-1e is supported thereby. The position of the end portion 70-2e of each beam part 70-2c is controlled by the corresponding beam support part 117, and the end portion 70-2e is supported thereby.
Instead of the above-described configuration, it is also possible to provide the arm parts 130 and 131 to the block body 61 and provide the recesses 68 and 69 to the alignment member 100.
(c) Welding Process
The welding process is performed using a welding jig (not graphically represented). As shown in
As shown in
The beam part 70-1c is narrow in width. However, as shown in
Further, as shown in
The electric welding of the each second signal wire 23-2 to the corresponding beam part 70-2c is performed in the same way as described above, so that the welded part 201 is formed.
As shown in
The welding of the drain wires 25 is performed as follows. As shown in
Thus, each drain wire 25 is welded to the Z1-side end surface part 80b1 of the corresponding projecting shield part 80b as described above.
The alignment member 100 is joined to the contact assembly 60, thereby forming the differential transmission cable connector temporary assembly 250 as a unit. The first and second signal wires 23-1 and 23-2 are maintained in positions near and opposite the beam parts 70-1c and 70-2c, respectively. The drain wires 25 are maintained in positions near and opposite the projecting shield parts 80b. Even in the case of turning the differential transmission cable connector temporary assembly 250 upside down to perform electric welding on the second signal wires 23-2, the positions of the second signal wires 23-2 relative to the beam parts 70-2c are maintained. Accordingly, there is no need to modify the positions of the first and second signal wires 23-1 and 23-2 and the drain wires 25 at the time of performing electric welding, so that electric welding is performed with efficiency. The number of processes of electric welding is reduced compared with that of soldering using a soldering iron.
As a result of the above-described processes, the differential transmission cable connector 50 is completed.
According to the present invention, the first and second signal wires 23-1 and 23-2 and the drain wires 25 of the differential transmission cable 20 are directly connected to the first and second signal contacts 70-1 and 70-2 and the ground contacts 80, respectively, of the contact assembly 60. Further, the rear ends of the ground contacts 80 extend further in the rear (Y1) direction than those of the first and second signal contacts 70-1 and 70-2. Accordingly, a better shield is provided between a differential signal transmission channel and another differential signal transmission channel adjacent thereto, thus resulting in better transmission characteristics. Therefore, this differential transmission cable connector 50 is employable for a high-speed signal transmission channel.
Further, the alignment member 100, aligning the pair wires 21 and the first and second signal wires 23-1 and 23-2 to the contact assembly 60, is joined to the contact assembly 60, thereby forming the differential transmission cable connector temporary assembly 250. Since electric welding is performed with respect to the temporary assembly 250, the welding of the first and second signal wires 23-1 and 23-2 to the first and second signal contacts 70-1 and 70-2 and the welding of the drain wires 25 to the ground contacts 80 can be performed with good operability.
Thus, the alignment member 100 to be connected to the contact assembly 60 is employed, and electric welding is performed with efficiency. As a result, the differential transmission cable connector 50 is manufactured with good productivity.
The present invention is not limited to the specifically disclosed embodiment, and variations and modifications may be made without departing from the scope of the present invention.
The present application is based on Japanese Priority Patent Application No. 2004-74922, filed on Mar. 16, 2004, the entire contents of which are hereby incorporated by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-074922 | Mar 2004 | JP | national |
