JP2008108671A - Branching connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce an area of a circuit board mounting a waveform shaping circuit to be arranged inside a branching connector and aim at downsizing of the branching connector. <P>SOLUTION: For the branching connector 10 to be provided at a position at which a plurality of branched lines are connected from a trunk line, a circuit board equipped with a conductive pattern of trunk-line wires 21 and branched line wires 22 is housed in a connector housing 11. The trunk-line wires 21 are connected with branched line wires 22 through a waveform shaping circuit 25 connecting resistors and coils in parallel, the waveform shaping circuit 25 has a gap each provided between the branched line wire 22 and the trunk-line wire 21, and a conductive adhesive 26 is applied to each gap to make up a resistance layer, and at the same time, a chip coil 27 is arranged on the surface of the resistance layer, electrodes at either end of the chip coil 27 are firmly adhered to the conductive adhesive 26 to make up a parallel circuit of the resistor and the coil. Further, the circuit board 20 has terminal materials 31 for the trunk line connected to the trunk-line wires 21 and terminal materials 32 for the branched lines connected to the branched line wires 22 set in protrusion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a branch connector, and more particularly, the connector has a function of attenuating reflection of a signal generated at a branch connection portion of a communication circuit, which is installed in an automobile and is installed in a LAN routed in the automobile. It is provided.

Conventionally, a connector is often used for connection between electric wires arranged in an automobile, and Japanese Patent Application Laid-Open No. 2006-4852 (Patent Document 1) provides a connector incorporating an electronic component.
As shown in FIG. 9, the connector 1 provided in Patent Document 1 accommodates a circuit board 6 in which a plurality of electronic components 5 are mounted in a housing 4 including an upper case 2 and a lower case 3, and the circuit board 6 The terminal 7 connected to is connected to the terminal of the terminal of the external electric wire (not shown).

Since the connector 1 provided in Patent Document 1 incorporates a circuit board 6 on which an electronic component 5 is mounted, the connector can have various functions, and the electronic component 5 is at a branch point of the communication circuit. When a waveform shaping circuit is configured by mounting a resistor and a coil, signal reflection at a branch point can be attenuated.
However, in order to configure the waveform shaping circuit, both the resistor 91 and the coil 92 must be mounted on the circuit board 6 as shown in FIG. 10A, and the area of the electronic component 5 mounting surface is large. The circuit board 6 is required.

The electronic components 5 such as the resistor 91 and the coil 92 are mounted on the circuit board 6 by soldering. In particular, in the chip-type electronic component 5, as shown in FIG. 10C, the solder 93 is printed on the land portion 94 provided in the conductor pattern 95 of the circuit board 6, and the electronic as shown in FIG. Electrodes (not shown) of the component 5 are joined to the solder 93, and the electronic component 5 and the conductor pattern 95 are electrically connected.
In order to ensure the bonding strength between the electronic component 5 and the land portion 94, it is necessary to secure the area of the land portion 94 on the circuit board 6 and increase the area where the land portion 94 and the solder 93 are in contact with each other. Therefore, a circuit board 6 having a large area is required, and there is a problem that the connector 1 that accommodates the circuit board 6 is enlarged.

JP 2006-4852 A

  The present invention has been made in view of the above problems, and in a branch connector, when a waveform shaping circuit for reducing signal reflection is provided at a branch point of a communication circuit, the area of a circuit board on which the waveform shaping circuit is mounted. The problem is to reduce the size of the branch connector and reduce the size of the branch connector.

In order to solve the above problems, the present invention is a branch connector provided at a position where a plurality of branch lines are branched and connected from a trunk line,
In a connector housing, a circuit board provided with a conductor pattern of a trunk line and a branch line is accommodated, and the trunk line is connected to the branch line via a waveform shaping circuit in which a resistor and a coil are connected in parallel.
The waveform shaping circuit is provided with a gap between the branch line and the main line, a conductive layer is applied to the gap to provide a resistance layer, and a chip coil is disposed on the surface of the resistance layer. The electrodes at both ends of the chip coil are fixed to the conductive adhesive to form a parallel circuit of the resistor and the coil,
A branch connector is provided in which a terminal material for a main line connected to the main line and a terminal material for a branch line connected to the branch line are projected from the circuit board.

In the branch connector of the present invention, a circuit board on which a waveform shaping circuit composed of a conductive adhesive as a resistance layer and a chip coil is mounted is accommodated in the connector housing, and the branch line is branched from the main line via the waveform shaping circuit. is doing.
The conductive adhesive and chip coil that make up the waveform shaping circuit are not mounted on the circuit board by soldering. Instead, the conductive adhesive is applied to the circuit board and the chip coil is placed on the surface of the conductive adhesive. The both ends of the chip coil are fixed to the conductive adhesive.
In general, a conductive adhesive has a lower electrical conductivity than a conductor pattern provided on a circuit board, so that the conductive adhesive functions as a resistance, and the conductive adhesive coating layer is used as a resistance layer. Therefore, as a matter of course, the conductive adhesive used in the present invention has a lower conductivity than the conductive pattern to be connected.
In this way, the chip coil is bonded to the surface of the conductive adhesive that becomes the resistance layer, and both ends of the chip coil are connected to the resistance layer, so that the main line and the branch line are connected in parallel. Are connected via a waveform shaping circuit.

In the present invention, as described above, the resistor and the coil are not separately mounted on the circuit board by soldering, and the chip coil is placed on the resistance layer so that the installation space is not required, and the circuit The size of the substrate can be reduced.
In addition, since the conductive adhesive is directly applied to the land portion provided in the conductor pattern, the contact area between the land portion and the conductive adhesive is larger than when a chip-type resistor is connected to the conductor pattern using solder. Even if it is at least, the bonding strength can be maintained.
For this reason, the area of a circuit board can be made smaller and a branch connector can be reduced in size.

The conductive adhesive is made of, for example, a material that is made conductive by blending a conductive metal such as platinum, gold, silver, copper, aluminum, or the like in the form of fine particles or filler into a polymer-based insulator. Yes.
As the polymer insulator, phenol resin, urea resin, polyester resin, epoxy resin, silicon resin, polyethylene, polystyrene, hard vinyl chloride, soft vinyl chloride, cellulose acetate, polyethylene terephthalate, fluororesin, raw rubber, soft rubber, Examples include ebonite, butyl rubber, neoprene rubber, and silicon rubber.

The impedance between the trunk / branch terminal material of the waveform shaping circuit comprising the conductive adhesive and the chip coil is 6% to 50%, preferably 10% to 22%, of the impedance (Z0) of the bus of the communication circuit used. It is preferable to do.
When the impedance is 6% or more, the reflection of the signal at the branch portion of the communication circuit can be attenuated. On the other hand, if it exceeds 50%, a voltage drop on the receiving side may be caused and a communication error may occur.

The resistance value of the waveform shaping circuit can be adjusted by changing the application amount of the conductive adhesive.
The resistance value of the conductive adhesive can be adjusted not by the application area of the conductive adhesive but by the application thickness. That is, when the application area of the conductive adhesive is constant, the resistance value can be reduced by increasing the thickness of the application of the conductive adhesive, while the thickness of the conductive adhesive is reduced. The resistance value can be increased.
In addition, when the thickness of the application of the conductive adhesive is constant, by increasing the area where the conductive adhesive is applied, the cross-sectional area can be increased and the resistance value can be reduced, while the application area is reduced. By doing so, the resistance value can be increased. However, if the coating area is increased, a space is taken, and it is preferable to adjust the resistance value by the coating thickness.

The connector housing is arranged in two upper and lower stages in the connector housing, and the main line terminal material or branch line terminal material is accommodated in each stage, and the circuit board is provided in the upper and lower two stage terminal accommodating chambers. One is provided on the end face side,
The trunk line and the branch line are made of a paired electric wire such as a twisted pair electric wire or a shielded twisted electric wire constituting a differential transmission line, and terminals connected to each terminal of the first communication line and the second communication line of the pair electric wire It is preferable that the main line terminal material or the branch line terminal material accommodated in each of the two-stage terminal accommodating chambers is connected.

  According to the above configuration, in the branch connector that is provided in the in-vehicle LAN and branches the branch line from the trunk line of the communication circuit, the conductive adhesive and the chip coil are disposed between the trunk line and the branch line of the circuit board. Since the waveform forming circuits connected in parallel are interposed, the conductive adhesive and the chip coil can attenuate the reflection of signals at an early stage.

  As described above, according to the branch connector of the present invention, since the chip coil is fixed to the surface of the conductive adhesive that is the resistance layer, it is not necessary to secure an area for the chip coil on the circuit board. . Furthermore, since the conductive adhesive is directly applied to the land portion of the conductor pattern, the bonding strength can be maintained even if the contact area between the conductive adhesive and the land portion is small. For this reason, the area of a circuit board can be made small and a branch connector can be reduced in size.

Embodiments of the present invention will be described with reference to the drawings.
1 to 7 show a branch connector 10 according to a first embodiment of the present invention.
As shown in FIG. 1, the branch connector 10 forms a branch portion 103 in which a plurality of branch lines 102 branch from a trunk line 101 in an in-vehicle LAN 100 that performs CAN communication (differential transmission method).

  As shown in FIGS. 2 and 3A and 3B, the branch connector 10 includes a connector fitting portion 16 provided on one side of the connector housing 11, and a circuit board 20 on the other side of the back side. A substrate housing portion 12 for housing is provided. The board accommodating portion 12 accommodates a circuit board 20 made of a printed circuit board, and a main line terminal material 31 and a branch line terminal material 32 that protrude from the circuit board 20 by soldering.

As shown in FIGS. 4, 6, and 7 (A), the rectangular circuit board 20 has a trunk line 21 (21-21) made of a conductor pattern along the upper and lower sides along the length direction. 1, 21-2), and a branch line 22 is provided in a central region sandwiched between the main lines 21. The branch line 22 is formed with a plurality of branch lines 22-1 facing the trunk line 21-1 at intervals in the length direction of the circuit board 20, and a plurality of branch lines facing the trunk line 21-2. 22-2 is similarly formed at intervals in the length direction.
The main line 21 is formed with land portions 21a at positions opposed to the plurality of branch line 22, respectively, while the land portions 22a are formed at the ends of the branch lines 22 on the main line side with gaps between the land portions 21a. is doing. A land portion 22b is also formed at the other end of each branch line 22, a terminal hole 23 is provided in the center of the land portion 22b, and the branch terminal material 32 is penetrated and soldered.
Terminal holes 24 are provided at both ends of the main line 21, respectively, and the main line terminal material 31 is penetrated and soldered.

Between each land part 21a of the trunk line 21-1 and each land part 22a of the plurality of branch lines 22-1, similarly, each land part 21a of the trunk line 21-2 and a plurality of branch lines 22-2. A waveform shaping circuit 25 shown in FIGS. 4 and 5 is provided between each land portion 22a, and the main line 21 is branched and connected to the branch line 22 via the waveform shaping circuit 25.
Each waveform shaping circuit 25 includes a conductive adhesive 26 which is a resistance layer, and a chip coil 27 bonded to the surface of the conductive adhesive 26.

As shown in FIGS. 6B and 7B, the conductive adhesive 26 is applied to the surfaces of the land portions 21a and 22a and the substrate surface in the gap therebetween with a required thickness.
As shown in FIG. 7C, the chip coil 27 is placed on the surface of the conductive adhesive 26, and the electrodes 27a at both ends of the chip coil 27 are fixed to the conductive adhesive 26 to conduct the conductive. The adhesive 26 and the chip coil 27 are connected in parallel.

Specifically, as shown in FIG. 7B, a conductive adhesive 26 is applied in a rectangular shape to each land portion 21a of the main line 21 and the land portion 22a of the branch line 22 that are arranged to face each other. 21 a and 22 a are electrically connected through the conductive adhesive 26. The width of the conductive adhesive 26 in the left-right direction X is made smaller than the width of the land portions 21a and 22a so as not to contact the conductive adhesive 26 applied between adjacent land portions.
The conductive adhesive 26 is made of a filler made of a conductive metal such as silver and kneaded with a thermosetting resin, and has a conductivity lower than that of the trunk line 21 and the branch line 22.

After the conductive adhesive 26 is applied, a chip coil 27 is placed and fixed on the surface in a state where the conductive adhesive 26 has adhesiveness. The chip coil 27 includes a pair of electrodes 27 a at both ends in the length direction, and the electrodes 27 a are fixedly connected to the conductive adhesive 26 to be electrically connected.
As described above, after the chip coil 27 is fixed to the conductive adhesive 26, the conductive adhesive 26 is cured by heating.

  The main line terminal material 31 is inserted by inserting the terminal holes 24 provided at both ends of the main line 21 (21-1, 21-2) and protruded by soldering, and the branch line 22 (22-1, 22-2). The branch terminal material 32 that is inserted into the terminal hole 23 provided at the other end and protruded by soldering is in the form of a rod made of a conductive metal material. Male terminal portions 31a and 32a are formed to be fitted and connected to the female terminals connected to the terminals of the wires of the branch circuit.

  As shown in FIGS. 2 and 3, the connector housing 11 that accommodates the circuit board 20 is a rectangular hollow portion that is long in the left-right direction X, and between the connector fitting portion 16 on the other side. A partition wall 13 is interposed between the upper and lower terminals through-holes 13 a communicating with the connector fitting portion 16 and the substrate housing portion 12. In addition, substrate locking step portions 12 a are provided on the inner surfaces of the upper, lower, left and right side walls of the substrate housing portion 12.

The circuit board 20 is inserted from the back side opening 12b of the board housing part 12, and the male terminal part 31a of the trunk line terminal material 31 protruding from the circuit board 20 is inserted into the left and right terminal through holes 13a-1 for branch lines. The male terminal portion 32a of the terminal material 32 is inserted into a terminal through hole 13a-2 provided between the terminal through holes 13a-1 on both sides.
The circuit board 20 is substantially the same size as the back side opening 12b, and the end of the circuit board 20 is held by the inner wall of the connector housing 11 and is locked by the board locking step 12a.

Further, a cover 40 for closing the back side opening 12b of the substrate housing portion 12 is provided. The cover 40 includes a side wall 40a that closes the rear side opening 12b and a peripheral wall 40b that protrudes from the peripheral edge of the side wall 40a, and is provided on the outer surface 11c of the connector housing 11 at a required position on the inner surface of the peripheral wall 40b as shown in FIG. A locking recess 40c for locking the locking protrusion 11a is provided.
The cover 40 is placed on the back side opening 12b of the board housing portion 12 of the connector housing 11, the locking projection 11 a of the connector housing 11 is locked to the locking recess 40 c of the cover 40, and the cover 40 is attached to the connector housing 11. ing.
Further, a lock portion 11b for fixing the connector housing 11 to the vehicle body is provided on the outer surface of the connector housing 11.

A plurality of connectors 50 shown in FIG. 3B are fitted in the connector fitting portion 16 of the branch connector 10 in a parallel state, and each of these connectors 50 is a twisted pair electric wire constituting a differential transmission line. 60.
Each connector 50 is provided with one upper and lower terminal accommodating chambers 52 (52A, 52B) in the connector housing 11, and the upper terminal accommodating chamber 52A is connected to the terminal of the first communication line 61 (CAN_H) of the twisted pair electric wire 60. While the connected female terminal 63A is inserted and locked, the terminal 63B connected to the terminal of the second communication line 62 (CAN_L) of the twisted pair electric wire 60 is inserted and locked in the lower terminal accommodating chamber 52B.

  An elastic locking piece 53 is provided on the surface of the connector housing 51, and a locking protrusion 54 provided on the outer surface of the elastic piece 53 is provided on the inner surface of the upper wall of the connector fitting portion 16 of the branch connector 10. It is set as the structure latched on 16a and lock-coupled.

In the branch connector 10 of the present invention having the above-described configuration, the chip coil 27 is fixed to the surface of the conductive adhesive 26 that is the resistance layer, and the resistor and the coil constituting the waveform shaping circuit are not arranged in parallel but are laminated. Therefore, it is not necessary to secure an area for the chip coil 24 on the circuit board 20.
In addition, since the conductive adhesive 26 is directly applied to the land portion and the substrate surface, the bonding strength can be maintained even if the contact area between the land portion and the conductive adhesive 26 is small as compared with the case where solder is used. For this reason, the circuit board 20 can be made small and the branch connector 10 can be reduced in size.

  In the present embodiment, since the twisted pair electric wire 60 constituting the differential transmission line is connected to the branch connector 10, the main line terminal material 31 or the branch line terminal material 32 is arranged in two stages in the connector housing 11. However, when connecting wires other than the pair wires, the main terminal material 31 or the branch terminal material 32 may be arranged in the connector housing 11 in one or more stages. The pair wires connected to the branch connector 10 are not limited to the twisted pair wires 60 but may be shielded twisted pair wires 60 or the like.

  FIG. 8A shows a first modification of the first embodiment. In the first embodiment, the width of the conductive adhesive 26 in the left-right direction X is smaller than the width of the land portions 21a and 22a, but is the same width.

FIG. 8B shows a second modification of the first embodiment.
In the second modification, the conductive adhesive 26 is not applied to the entire surface between the land portions 21a and the land portions 22a opposed to each other with a gap, but the conductive adhesive 26A is provided on both sides with a space therebetween. 26B is applied to connect the land portion 21a and the land portion 22a.
The chip coil 24 is adhered to the surfaces of the two conductive adhesives 26A and 26B, and the pair of electrodes 27a of the chip coil 27 are electrically connected to both the conductive adhesives 26A and 26B, respectively.
Since the conductive adhesives 26A and 26B function as resistors, the two resistors are connected in parallel, and the resistance value can be made smaller than mounting one rectangular conductive adhesive 26 of the same shape. The resistance value can be adjusted. Further, the conductive adhesives 26A and 26B and the chip coil 24 are connected in parallel.
In addition, since another structure and an effect are the same as that of 1st Embodiment, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The present invention is not limited to the above-described embodiments, and includes various forms within the scope of the claims of the present invention.

It is the schematic which shows the branch part formed with the branch connector of this invention. It is sectional drawing in the state which fitted the other party connector to the branch connector of 1st Embodiment of this invention. (A) is an exploded perspective view of a branch connector, (B) is a perspective view of the connector inserted in a connector fitting part. It is a top view of a circuit board. It is II sectional drawing of a circuit board. (A) is the figure which showed the trunk line and branch line on a circuit board, (B) is the figure which showed application | coating with the conductive adhesive. (A)-(C) are explanatory drawings which apply | coat a conductive adhesive to a circuit board, and adhere a chip coil. It is a figure which shows the modification of 1st Embodiment. It is a figure which shows a prior art example. It is a figure which shows another prior art example, (A) is a top view, (B) is BB sectional drawing, (C) is the principal part enlarged view which mounted the solder on the circuit board, (D) is a circuit board. It is the principal part enlarged view which mounted resistance and a coil.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Branch connector 11 Connector housing 12 Board | substrate accommodating part 12a Board | substrate latching step part 13 Partition wall 13a Terminal through hole 16 Connector fitting part 20 Circuit board 21 Trunk line 22 Branch line 21a, 22a Land part 23 Through hole 25 Waveform shaping circuit 26 Conductive adhesive 27 Chip coil 31 Terminal material for trunk line 32 Terminal material for branch line

Claims (3)

A branch connector provided at a position for branch connection of a plurality of branch lines from a main line,
In a connector housing, a circuit board provided with a conductor pattern of a trunk line and a branch line is accommodated, and the trunk line is connected to the branch line via a waveform shaping circuit in which a resistor and a coil are connected in parallel.
The waveform shaping circuit is provided with a gap between the branch line and the main line, a conductive layer is applied to the gap to provide a resistance layer, and a chip coil is disposed on the surface of the resistance layer. The electrodes at both ends of the chip coil are fixed to the conductive adhesive to form a parallel circuit of the resistor and the coil,
A branch connector characterized in that a branch line terminal material connected to the branch line and a branch line terminal material connected to the branch line are provided on the circuit board.   The branch connector according to claim 1, wherein a resistance value is adjusted by an application amount of the conductive adhesive. A board housing portion is arranged in parallel in the connector housing, and the circuit board and the trunk line terminal material or branch line terminal material connected to the circuit board are housed,
The trunk line and the branch line are made of a paired electric wire such as a twisted pair electric wire or a shielded twisted electric wire constituting a differential transmission line, and the terminal connected to each terminal of the first communication line and the second communication line of the pair electric wire is the main line. The branch connector according to claim 1, wherein the branch connector is configured to be connected to the terminal material for branch or the terminal material for branch line.

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