JP5530678B2 - Branch connector - Google Patents

Description

  The present invention relates to a branch connector capable of connecting a plurality of plugs to which at least a pair of signal lines are connected, and an information transmission apparatus configured by connecting a plurality of plugs thereto.

  2. Description of the Related Art Conventionally, a branch connector in which a plurality of communication lines (for example, twisted pair cables) are connected via plugs is used in an in-vehicle information communication system such as a CAN (Controller Area Network) or a FlexRay. For example, in CAN communication, one signal line of a twisted pair cable transmits an H signal, the other transmits an L signal, and a signal is transmitted by the potential difference.

  As an example of a branch connector, an invention has been disclosed regarding a branch connector in which transmission lines having terminal plugs provided at the ends of a plurality of communication lines are connected from opposite directions (see, for example, Patent Document 1). ). In view of the difficulty in impedance matching at the branch point, this branch connector incorporates a low-pass filter composed of a resistor and a coil connected in parallel to reduce high-frequency noise caused by signal reflection. Moreover, it is set as the structure which a plug fits from the mutually opposing direction, and the resistor and coil which comprise a filter are arrange | positioned with high density.

JP 2008-41287 A

  However, in the above-described conventional branch connector, the axial direction of the coils of the low-pass filter faces the same direction. Therefore, when a magnetic field is generated around the branch connector, the coils may be adversely affected all at once.

  Such an adverse effect is caused by a phenomenon that, when a magnetic field is generated in the same direction as the axial direction of the coil, the inductance of the coil is reduced due to magnetic saturation, and the waveform distortion reducing effect of the filter is reduced. The amount of change in the inductance of the coil is determined by the magnitude of the magnetic flux passing through the cross section of the coil. Therefore, it changes depending on the angle formed by the coil axial direction and the magnetic field direction, and is maximized when a magnetic field is generated in the same direction as the coil axial direction. For this reason, if the axial directions of the coils are aligned, the performance of attenuating the high-frequency signal of the filter may be reduced at the same time, causing a communication error.

  Therefore, in the conventional branch connector, the noise attenuation effect of the low-pass filter is lowered, and there is a risk of causing a communication error.

  The present invention is for solving such problems, and a main object thereof is to provide a branch connector capable of suppressing the influence of a generated magnetic field.

In order to achieve the above object, the first aspect of the present invention provides:
A branch connector capable of connecting a plurality of plugs to which a cable including at least a pair of signal lines is connected,
A first contact member connected to a plug-side contact member connected to one of the pair of signal lines, and a second contact member connected to a plug-side contact member connected to the other of the pair of signal lines. A contact member, a first filter section having a coil and a resistance, one end connected to the first contact member, and a second filter section having a coil and a resistance, one end connected to the second contact member A plurality of connection units having a filter section;
A substrate to which the other ends of the first filter unit and the second filter unit in each connection unit are connected;
A housing for housing the plurality of connection units and the substrate;
The coil of the first filter part and the coil of the second filter part have a substantially right angle in the axial direction .
The substrate includes a first substrate connected to the first filter unit, and a second substrate connected to the second filter unit,
The first substrate and the second substrate have a two-layer structure ,
It is a branch connector.

  According to the first aspect of the present invention, the coil of the first filter section and the coil of the second filter section are substantially perpendicular to each other in the axial direction. Even if a strong magnetic field is generated, the axial direction of either the first filter coil or the second filter coil does not have to be the same as the magnetic field. As a result, the performance of either the coil of the first filter unit or the coil of the second filter unit is maintained high. Therefore, the influence of the generated magnetic field can be suppressed.

The second aspect of the present invention is:
A branch connector according to the first aspect of the present invention ,
Of the first filter units in each of the connection units connected to the first substrate, the coils of the first filter units adjacent to each other, and the coils connected to the second substrate, Of the second filter portions in each connection unit, the coils of the second filter portions adjacent to each other are branch connectors characterized in that the angle formed in the axial direction is substantially a right angle .

  According to the second aspect of the present invention, since the branch connector according to the first aspect of the present invention is provided, the influence of the generated magnetic field can be suppressed.

  According to the present invention, it is possible to provide a branch connector capable of suppressing the influence of the generated magnetic field, and an information transmission apparatus configured by connecting a plurality of plugs thereto.

It is a disassembled perspective view which shows the structure of the branch connector 10 which concerns on one Example of this invention, and the information transmission apparatus 1. FIG. 1 is a circuit diagram of a branch connector 10 and an information transmission apparatus 1 configured by connecting a plurality of plugs 50 to the branch connector 10. It is a figure which shows the analysis result that the inductance of a coil falls by generation | occurrence | production of a magnetic field. Attenuation of high frequency signal when using a filter whose coil inductance is not reduced (= 480 [nH]) and attenuation of high frequency signal when using a filter whose coil inductance is reduced to 420 [nH] FIG. In the branch connector 10, a configuration example from the first contact 22A to which the signal line 52A is connected to the substrate 30 and a configuration example of the coil 26A are shown. In the branch connector 10, a configuration example from the second contact 22B to which the signal line 52B is connected to the substrate 30 is shown. It is a figure which shows the virtual information transmission apparatus made into experiment object. In the virtual apparatus shown in FIG. 7, (1) normal time, (2) magnetic field generation (when the branch connector 10 of this embodiment is used), (3) magnetic field generation (coil axial direction is one). It is a figure which shows each signal voltage transition in the case of using the connector which has faced the direction. It is a disassembled perspective view which shows the structure of the branch connector which concerns on the other Example of this invention, and an information transmission apparatus. 9 illustrates a configuration example from the first contact 22A to which the signal line 52A is connected to the substrate 30 among the branch connectors illustrated in FIG. 9 illustrates a configuration example from the first contact 22A to which the signal line 52A is connected to the substrate 30 among the branch connectors illustrated in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.

  Hereinafter, a branch connector and an information transmission apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is an exploded perspective view showing configurations of a branch connector 10 and an information transmission apparatus 1 according to an embodiment of the present invention. The information transmission apparatus 1 is configured by connecting a plurality of plugs 50 to the branch connector 10. The information transmission apparatus 1 includes a CAN (Controller Area Network), a low-speed body communication protocol typified by LIN (Local Interconnect Network), a multimedia communication protocol typified by MOST (Media Oriented Systems Transport), FlexRay, etc. It is suitable for performing communication using an appropriate communication protocol.

  First, the plug 50 will be described. A cable 52 including a pair of signal lines 52A and 52B is connected to the plug 50. The cable 52 is, for example, a twisted pair cable, and a pair of copper core wires, a resin insulator, a ground wire (not shown), and the like that become the signal lines 52A and 52B are included in a resin protective film. The cable 52 has one end connected to the contact member of the plug 50 and the other end connected to a control device such as an ECU (Electronic Control Unit), sensors, and the like.

  The branch connector 10 has a structure in which a plurality of connection units 20 are attached to a substrate 30. Each connection unit 20 includes a first contact 22A, a second contact 22B, and filters 24A and 24B. When the plug 50 is attached to the branch connector 10, the first contact 22A and the second contact 22B are connected to each of the pair of signal lines 52A and 52B via a plug-side contact member.

  Here, there are various types of knife-fork, bellows, and the like in the connection mode between the plug-side contact member and the first contact 22A and the second contact 22B, but there is no particular limitation on the application of the present invention. .

  The filter 24 </ b> A has one end connected to the first contact 22 </ b> A and the other end connected to the electrode of the substrate 30. Similarly, the filter 24B has one end connected to the first contact 22B and the other end connected to the electrode of the substrate 30.

  The filter 24A is, for example, a known low-pass filter in which a resistor 25A and a coil 26A are connected in parallel. Similarly, the filter 24B is a known low-pass filter in which a resistor 25B and a coil 26B are connected in parallel, for example.

  The plurality of connection units 20 and the substrate 30 are accommodated in the housing 40. The housing 40 is formed by molding a thermoplastic resin such as LCP, and is formed with insertion holes for inserting bolts and screws for attaching the substrate 30.

  With such a configuration, the device connected to the plug 50 and the cable 52 connected to a certain connection unit 20 is connected to the device connected to the plug 50 and the cable 52 connected to another connection unit 20 via the substrate 30. Signals and power can be transmitted and received. However, when the number of connection units 20 is large, the impedance at the branch point decreases, so that negative reflection occurs and waveform distortion occurs in the communication waveform. This waveform distortion has a higher frequency than the frequency band forming the communication signal. For this reason, the filters 24A and 24B are configured as low-pass filters to reduce waveform distortion.

  FIG. 2 shows, in the form of a circuit diagram, such a branch connector 10 and the information transmission apparatus 1 configured by connecting a plurality of plugs 50 to the branch connector 10.

  By the way, as a problem of the filter having such a configuration, particularly when a magnetic field is generated in the same direction as the axial direction of the coil, the inductance of the coil is lowered due to magnetic saturation, and the waveform distortion reducing effect of the filter is lowered. Exists.

  FIG. 3 is a diagram showing an analysis result that the inductance of the coil decreases due to the generation of the magnetic field. Here, an inductor having an inductance of 480 [nH] without a magnetic field was used. FIG. 4 shows a case where a high-frequency signal attenuation when using a filter in which the coil inductance is not reduced (= 480 [nH]) and a filter in which the coil inductance is reduced to 420 [nH] are used. It is the figure which compared the attenuation amount of the high frequency signal. As shown in the figure, it can be seen that the performance of the filter for attenuating the high-frequency signal decreases as the inductance of the coil decreases.

  The amount of change in the inductance of the coil is determined by the magnitude of the magnetic flux passing through the cross section of the coil. Therefore, it changes depending on the angle formed by the coil axial direction and the magnetic field direction, and is maximized when a magnetic field is generated in the same direction as the coil axial direction. For this reason, if the axial directions of the coils are aligned, the performance of attenuating the high-frequency signal of the filter may be reduced at the same time, causing a communication error.

  Therefore, the branch connector 10 of the present embodiment is configured such that the angle formed by the axial direction of the coil 26A of the filter 24A and the coil 26B of the filter 24B is substantially a right angle.

  FIG. 5 shows a configuration example of the branch connector 10 from the first contact 22A to which the signal line 52A is connected to the substrate 30 and a configuration example of the coil 26A. 6 and 6 are based on the premise that the substrate 30 has a partial two-layer structure (the two-layer portions are the substrates 30A and 30B, respectively), but the present invention is not limited to this. Not. The coil 26A is housed in a mold resin 26Aa and has a winding 26Ad connected to the electrode 26Ab and a core 26Ac such as a ferrite around which the winding 26Ad is wound. The axial direction of the coil 26A faces the direction (X direction in the drawing) from the first contact 22A toward the substrate 30A.

  FIG. 6 shows a configuration example of the branch connector 10 from the second contact 22B to which the signal line 52B is connected to the substrate 30. The axial direction of the coil 26B is directed in the direction from the second contact 22B toward the substrate 30B (Y direction in the figure).

  The coils 26A and 26B only have to have a substantially right angle in the axial direction, and as shown in FIGS. 5 and 6, the longitudinal direction does not have to be a substantially right angle.

  By configuring the branch connector 10 in this way, even if a strong magnetic field is generated in the environment where the branch connector 10 is placed, either of the coils 26A and 26B does not have the same axial direction as the magnetic field. Therefore, the waveform distortion reduction effect is maintained high. Therefore, the influence of the generated magnetic field can be suppressed.

  7 and 8 are explanatory diagrams for illustrating the effect of the branch connector 10 of the present embodiment. FIG. 7 shows a virtual information transmission apparatus as an experiment target. As shown in the figure, the length of the cable 62 from the transmission side node 60 to the branch connector 64 and the length of the cable 62 from the branch connector 64 to the reception side node 60 are both 4 [m].

  FIG. 8 shows the virtual device shown in FIG. 7, in which (1) normal operation, (2) magnetic field generation (when the branch connector 10 of this embodiment is used), and (3) magnetic field generation (coil It is a figure which shows each signal voltage transition in the case of using the connector where an axial direction has turned to one direction.

  As shown in FIG. 8, in the case of (3) above, the signal determination voltage (denoted as the high level determination voltage in the figure) is reached even after the determination timing denoted as the high level determination timing in the figure. However, in the case of (2) above, since the signal determination voltage is not reached, the communication error can be avoided.

  Note that this determination timing is the timing when high-frequency noise caused by reflection due to impedance mismatch at the branch point has elapsed from the timing at which the signal is recognized by the receiving side, and after this time has been attenuated by the low-pass filter. The signal is discriminated. The determination timing is determined by the above-described protocol such as CAN.

  In addition, by making the angle between the coil 26A of the filter 24A and the coil 26B of the filter 24B substantially perpendicular, it is possible not only to suppress the influence of the magnetic field but also to suppress the decrease in inductance due to the mutual inductance. .

  According to the branch connector 10 of the present embodiment described above, the angle formed by the axial direction of the coil 26A of the filter 24A and the coil 26B of the filter 24B is substantially a right angle. Even in the case where a strong magnetic field is generated in the exposed environment, one of the coils 26A and 26B does not have to have the same axial direction as the magnetic field. As a result, the waveform distortion reducing effect of either one of the coils 26A and 26B is maintained high. Therefore, the influence of the generated magnetic field can be suppressed.

  The best mode for carrying out the present invention has been described above with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the present invention. And substitutions can be added.

  For example, in FIG. 1 and the like, an example in which four connection units 20 are provided in parallel is illustrated, but the number of connection units 20 is not particularly limited.

  Moreover, it is not necessary to fit the plug 50 from the same direction, and it is good also as a structure which can be fitted from both sides, as shown in FIG. FIG. 9 is an exploded perspective view showing configurations of a branch connector and an information transmission device according to another embodiment of the present invention. FIG. 10 shows a configuration example from the first contact 22A to which the signal line 52A is connected to the substrate 30 among the branch connectors shown in FIG. 9, and FIG. Of the illustrated branch connectors, a configuration example from the first contact 22A to which the signal line 52A is connected to the substrate 30 is shown.

  The present invention can be used in the automobile manufacturing industry, the automobile parts manufacturing industry, and the like.

DESCRIPTION OF SYMBOLS 1 Information transmission apparatus 10 Branch connector 20 Connection unit 22A 1st contact 22B 2nd contact 24A, 24B Filter 25A, 25B Resistance 26A, 26B Coil 30, 30A, 30B Board | substrate 40 Housing 50 Plug 52 Cable 52A, 52B Signal line 60 node

Claims (2)

A branch connector capable of connecting a plurality of plugs to which a cable including at least a pair of signal lines is connected,
A first contact member connected to a plug-side contact member connected to one of the pair of signal lines, and a second contact member connected to a plug-side contact member connected to the other of the pair of signal lines. A contact member, a first filter section having a coil and a resistance, one end connected to the first contact member, and a second filter section having a coil and a resistance, one end connected to the second contact member A plurality of connection units having a filter section;
A substrate to which the other ends of the first filter unit and the second filter unit in each connection unit are connected;
A housing for housing the plurality of connection units and the substrate;
The coil of the first filter part and the coil of the second filter part have a substantially right angle in the axial direction .
The substrate includes a first substrate connected to the first filter unit, and a second substrate connected to the second filter unit,
The first substrate and the second substrate have a two-layer structure ,
Branch connector. Of the first filter units in each of the connection units connected to the first substrate, the coils of the first filter units adjacent to each other, and the coils connected to the second substrate, Of the second filter portions in each connection unit, the coils of the second filter portions adjacent to each other are characterized in that the angle formed in the axial direction is substantially a right angle.
The branch connector according to claim 1.