JP2012070100A - Network apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide optimum connection in dividing a board and connecting the same in a network signal, in a network apparatus.SOLUTION: The network apparatus comprising a network interface is provided with: a first board provided with a LAN connector and a pulse transformer; and a second board provided with a physical layer controller (PHY) and a network processing part. The pulse transformer provided to the first board and the physical layer controller provided to the second board are interconnected via a connection cable.

Description

  The present invention relates to a network device such as a network camera, and more particularly to an interface portion having a pan / tilt mechanism and connected to a network.

  Conventionally, when a network device is connected to a network, a LAN connector, a pulse transformer for insulation from the outside, a physical layer controller (PHY), and a network control chip are connected within a short distance in the network device. Yes. In this case, when connecting to the outside via a LAN connector, the inside and the outside are insulated by a pulse transformer arranged in the immediate vicinity of the LAN connector so as to protect the inside. That is, it is only necessary to take a creeping distance so as to separate only a limited area, which is the primary side of the pulse transformer arranged closest to the LAN connector, from the secondary side. Furthermore, various cables and devices conforming to the standard are connected to the outside of the device. In order to guarantee communication against these, the above creepage distance is ensured in order to eliminate as much as possible factors that degrade signal quality (for example, signal line impedance mismatch, noise leakage, etc.).

  For example, conventionally, a network camera having a pan / tilt mechanism has a block configuration as shown in FIG. That is, it includes a lens unit 100, a movable part substrate 206 that performs video signal processing, and a fixed part substrate 306 for receiving a video signal, performing network processing, and connecting to a LAN.

  The lens unit 100 includes a lens 110, a sensor 120, and a motor 130. The movable part substrate 206 includes a video processing part 210, a second individual power supply part 256, and a connector 246. The fixed unit substrate 306 includes a connector 356, a network processing unit 220, a physical layer controller (PHY) 230, a pulse transformer 340, a LAN connector 330, a first individual power supply unit 311, and a PoE power supply unit 310.

  A portion connecting the movable portion substrate 206 and the fixed portion substrate 306 passes through a signal line 376 for a high-speed video signal / communication signal and a signal line 386 for a power supply signal for supplying power to the movable portion.

  There is also a block configuration as shown in FIG. That is, the fixed board 308 includes a LAN connector 330 and a power connector 320 that need to be connected to the outside, and a movable board 208 and a connector 248 for connection. On the other hand, the movable part substrate 208 includes a video processing part 210, a network processing part 228, a physical layer controller (PHY) 230, a pulse transformer 340, a fixed part board 308 and a connector 248 for connection. Furthermore, the movable part substrate 208 includes a PT control part 268 for pan / tilt control, a pan / tilt driving motor 408, a third individual power supply part 251, and a power supply part 318. Then, a signal line 378 and a power signal line 388 for supplying power to the movable part were passed through a cable connecting the fixed part substrate 308 and the movable part substrate 208.

  Further, Patent Document 1 discloses an interface module in which a pulse transformer and a noise filter are integrated.

No. 07-022914

  However, in the configuration of the prior art according to FIG. 7 described above, the video signal data rate is about 27 Mbyte / second for the NTSC class, about 111 Mbyte / second for 1280 * 960, and about 150 Mbyte / second for full HD. . When this data rate is transmitted in 8-bit parallel, the number of signal lines including the clock increases to 18 to transmit as a differential signal. When an 8-bit parallel differential signal is serialized and transmitted, the number of signal lines is reduced, but the signal frequency is increased. When 8-bit parallel is serialized and passed as a single signal, the signal rate is 8 times.

  That is, the signal is about 216 Mbit / sec in the NTSC class, about 890 Mbit / sec in 1280 * 960, and about 1.2 Gbit / sec in full HD, which is a very high speed signal. In addition, this signal has a length of several tens of centimeters even in the network camera device because the movable part for performing pan / tilt and the fixed part are connected. When a high-speed signal exceeding 200 MHz is transmitted by a cable or FPC, the signal quality is deteriorated and radiation noise is increased, and the cost for countermeasures is increased, and a large space is required on the board and the mechanical mechanism. .

  The above-described prior art shown in FIG. 8 is a technique for transmitting a LAN signal connected from the outside directly to a movable part via a connector and a cable. According to this method, for example, in the case of 100Base-T, the signal frequency is 125 MHz. In the case of 100Base-T, the number of signal lines is a differential signal for both transmission and reception, and is four. Further, when PoE (Power over Ethernet (registered trademark)) is supported, the number is six.

  However, in the case of the configuration shown in FIG. 8, the 100Base-T cable is directly pulled into the interior and further connected to the pulse transformer 340 and the physical layer controller (PHY) 230 via the internal wiring. The LAN connector 330, the connector 358, the signal line 378, the connector 248, and the pulse transformer 340 inside the device are directly connected from the outside. In this case, it is necessary to perform impedance matching including a cable or the like that is allowed by the standard of 100Base-T, and it is very difficult to ensure signal quality. Further, since the inside and the outside must be insulated for LAN connection, everything from the LAN connector 330 in the device to the primary side of the pulse transformer 340 must have a creepage distance from the secondary side. In other words, the area for securing the creepage distance increases, which means that the arrangement in the equipment can be restricted, and the equipment becomes larger accordingly.

  In the interface module of Patent Document 1, an interface module in which a pulse transformer and a noise filter are integrated is disclosed. This interface module is a small board module arranged between a LAN connector arranged on a main board (single-sided board) and a physical layer controller (PHY), and is a small board superimposed on the board. The purpose is to reduce the crosstalk by separating the transmission / reception system on this small substrate, to reduce the space by arranging noise filters on both sides, and to combine the characteristics of both transmission and reception.

  However, a LAN connector, a pulse transformer, a noise filter, a physical layer controller (PHY), and a network processing unit are originally mounted on a single substrate. On the other hand, in the configuration of Patent Document 1, the pulse transformer and the noise filter are separated as a small board and mounted so as to be superimposed on the original board. For this reason, it is not assumed that the board on which the main processing system is mounted and the LAN connector for connecting to the outside are arranged separately.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide an optimal connection when a substrate is divided in a network signal system and connected in a network device.

That is,
(1) Suppress radiation noise by reducing the frequency of the transmission signal and reducing the number of signal lines,
(2) Easy impedance matching and easy signal quality.
(3) Miniaturization of the device by minimizing the creeping distance area;
It is to provide a network device such as a network camera.

In order to achieve the above object, a network device according to the present invention comprises the following arrangement. That is,
A network device having a network interface,
A first substrate comprising a LAN connector and a pulse transformer;
A second substrate including a physical layer controller and a network processing unit,
The pulse transformer included in the first substrate and the physical layer controller (PHY) included in the second substrate are connected by a connection cable.

  According to the present invention, it is possible to provide a network device that suppresses radiation noise by reducing the frequency of a transmission signal and reducing the number of signal lines, facilitates impedance matching, and easily ensures signal quality. In addition, it is possible to provide a network camera that can reduce the size of the apparatus while minimizing the area taken by the creepage distance.

1 is a block diagram of a network camera according to a first embodiment. 1 is a conceptual diagram of a pan / tilt camera of Embodiment 1. FIG. FIG. 3 is a block diagram of a fixing unit according to the first embodiment. FIG. 6 is another block diagram of the fixing unit of the first embodiment. It is a block diagram of the network camera of Embodiment 2. FIG. 6 is a block diagram of a fixing unit according to a second embodiment. It is a block diagram of a 1st prior art example. It is a block diagram of a 2nd prior art example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Embodiment 1>
The configuration of the network device according to the first embodiment of the present invention will be described. In the first embodiment, a network camera will be described as an example of a network device having a network interface.

  FIG. 1 is a block diagram of a network camera according to a first embodiment of the present invention.

  In FIG. 1, 100 is a lens unit of a network camera, 200 is a movable part substrate (second substrate) for performing video signal processing, and 300 is a fixed part substrate (first substrate) for connecting to a LAN.

  The lens unit 100 includes a lens 110 for capturing an image, a sensor 120 for detecting an image captured by the lens 110, and a motor 130 for driving the lens 110. The movable part substrate 200 includes a video processing unit 210, a network processing unit 220, a physical layer controller (PHY) 230, a connector 240, and an individual power supply unit 250. The fixed part substrate 300 includes a connector 350, a pulse transformer 340, a LAN connector 330, and a PoE power supply part 310.

  The video signal picked up by the sensor 120 via the lens 110 of the lens unit 100 is transmitted to the video processing unit 210 of the movable part substrate 200 to be processed, and the network processing unit 220 performs packetization, protocol processing, and the like. Is called. The protocol-processed video signal is converted by a physical layer controller (PHY) 230 into a signal form that can be flowed on the network. After that, the connector 240 and the signal line 370 are passed through the pulse transformer 340 via the connector 350 of the fixed portion substrate 300, and the LAN connector 330 is connected to the external device. Here, the individual power supply unit 250 supplies power to each of the video processing unit 210, the network processing unit 220, and the physical layer controller (PHY) 230.

  When power is supplied from the LAN cable by PoE, power is supplied from the LAN connector 330 and the pulse transformer 340 to the PoE power supply unit 310, and the PoE power supply unit 310 generates necessary power in the device. The The PoE power supply unit 310 supplies power to the movable unit via the connector 350 and the signal line 380.

  Next, a network camera having a pan / tilt mechanism for changing the imaging direction will be described. FIG. 2 is an explanatory diagram of a network camera 400 having a pan / tilt mechanism.

  FIG. 2A is a side view of the network camera 400, and the rotation mechanism of the pan mechanism is composed of a bottom case 410 and a turntable 412, and the turntable 412 rotates around a pan rotation shaft 414.

  FIG. 2B is a front view of the network camera 400, and the rotation part of the tilt mechanism is configured by the lens column 420 and the lens case 430, and the lens case 430 and the lens unit 100 rotate around the tilt rotation shaft 425. It is.

  The fixed part substrate 300 (FIG. 1) is disposed in the bottom case 410 and does not move even when the pan / tilt mechanism is operated. On the other hand, the movable part substrate 200 is fixed to the turntable 412, and is movable along with the rotation operation of the pan mechanism. When the turntable 412 rotates about ± 180 °, the connection cables (signal lines 370 and 380 in FIG. 1) that connect the movable part substrate 200 (FIG. 1) and the fixed part substrate 300 (FIG. 1) Must be configured to absorb rotation. For this purpose, it is loosely wound 2-3 times around a bobbin (not shown) provided around the pan rotation shaft 414 so as to be able to absorb the expansion and contraction when rotating. Here, this connection cable is 40-50 cm, and FPC is used in consideration of durable operation and cost.

  In the first embodiment, a case where a network camera is connected to a 100Base-T network will be described as an example. In a 100Base-T network, transmission data / reception data are transmitted and received as differential signals, and therefore, there are two signal pairs used for communication, four. In FIG. 1, four signals pass through the physical layer controller (PHY) 230, the connector 240, the signal line 370, the connector 350, the pulse transformer 340, and the LAN connector 330, and the signal frequency is 125 MHz. Since this line is a signal that compresses the video signal and flows it through the network, the signal frequency is constant regardless of the video size. For the reference, the signal line 376 in the conventional example of FIG. 7 described above for reference is, when in full HD size, the number of signal lines is 18 and the signal frequency is about 150 MHz in parallel, and the number of signal lines is 4 and the signal frequency is about serial when serial. 1.2 GHz.

  FIG. 3 is a block diagram of the fixed part substrate 300. 3, 330 is a LAN connector, 340 to which a bias 360 is applied is a pulse transformer, 350 is a connector for connecting to the movable part substrate 200 (FIG. 1), and 310 is a PoE power source. Here, the LAN connector 330 is an 8-pole connector for 100Base-T. Therefore, the LAN connector 330 includes differential TX + signal lines 331, TX− signal lines 332, RX + signal lines 333, RX− signal lines 334, and power input lines 335-336 and 337-338 that can supply power according to the PoE standard. Prepare. The TX + signal line 331, the TX− signal line 332, the RX + signal line 333, and the RX− signal line 334 used for transmission / reception are connected to the primary side of the pulse transformer 340. Transmission / reception signal lines 341 to 344 from the secondary side insulated by the pulse transformer 340 are connected to the physical layer controller (PHY) 230 (FIG. 1) of the movable part substrate 200 (FIG. 1) via the connector 350.

  The transmission / reception signal that has entered the pulse transformer 340 from the LAN connector 330 is extracted from the center tap of the pulse transformer 340 because the power from the PoE power supply unit 310 is superimposed. Then, the power is supplied to the insulated power supply unit 314 of the PoE power supply unit 310 through the diode bridge 316. Further, the power superimposed on the power input lines 335-336 and 337-338, which are empty lines of the LAN connector 330, is supplied to the insulated power supply 314 of the PoE power supply 310 through the diode bridge 317.

  The PoE standard (IEEE 802.3af) recognizes both the signal line superposition type that places power on the TX / RX line and the idle line superposition type that places power on the empty line when power is supplied from the HUB (not shown). Yes. For this reason, on the network equipment side, it is necessary to support both the signal line superposition type and the empty line superposition type. For this reason, as shown in FIG. 3, two systems (diode bridges 316 and 317) for superimposing signal lines and vacant lines are provided as diode bridges so that power can be supplied from either of them. The insulated power supply unit 314 insulates the inside / outside of the power supply (standard 48V) supplied from the network by a transformer and generates the necessary power supply (in this case, 5V).

  Here, with respect to a signal input from the outside on the LAN connector 330 side, it is necessary to provide a dielectric breakdown voltage of 1500 V with the internal circuit. For this reason, the primary side elements such as the LAN connector 330, the pulse transformer 340, and the diode bridge are arranged around the LAN connector 330 so as to have a creepage distance between the secondary side elements. .

  Further, when performing communication based on 100Base-T, it is necessary to ensure the signal quality of the TX / RX line according to the LAN standard. For this purpose, the pulse transformer 340 is disposed in the immediate vicinity of the LAN connector 330 so that the differential lines are short and connected with equal length wiring.

  In the first embodiment, a 100Base-T network is described as an example. However, it goes without saying that the present invention is not limited to 100Base-T, and can be applied to a 1000Base-T gigabit network.

  FIG. 4 shows a block diagram of the fixed part substrate 300 when a 1000Base-T network is used.

  Reference numeral 330 denotes a LAN connector similar to the 100Base-T configuration, and 390 denotes a pulse transformer corresponding to four 1000Base-T pairs. Further, 350 is a connector for providing four pairs of communication lines for 1000Base-T to the movable part, and 396 is an insulated power supply unit corresponding to PoE for 1000Base-T. In the 1000Base-T network, 4 pairs of signal lines and 8 lines on the LAN connector 330 are used, respectively, and the signal frequency is 125 MHz, which is the same as 100Base-T. Since 1000Base-T uses all four pairs and eight lines, the LAN connector 330, the pulse transformer 390, and the connector 350 that transmits a communication signal to the movable part all correspond to four pairs. The number of pins of the connector 350 is ten in total because two signal lines for sending power are required in addition to the eight communication lines. As for the communication line, the pulse transformer 340 to the physical layer controller (PHY) 230 in 100Base-T has two pairs and four in 100Base-T, but four pairs and eight in 1000Base-T.

  As described above, according to the first embodiment, when connecting the fixed unit substrate and the movable unit substrate in the network device, the LAN connector and the pulse transformer are arranged on the fixed unit substrate. A physical layer controller (PHY) and a network processing unit are arranged on the movable part substrate. Thereby, the signal frequency of the line connecting the various components of the network device can be kept low, and the number of signal lines can be reduced.

  In addition, with such a configuration, the cable cost can be reduced, and by placing the power supply unit on the fixed part substrate, a large and heavy transformer can be arranged on the fixed part side, and is movable. It is possible to reduce the size and weight of the part. In addition, it is possible to reduce the size of the motor that drives the movable part. Furthermore, radiation noise can be easily suppressed. Further, since the portion that needs to be insulated can be concentrated on a partial region of the fixed portion substrate, the size can be easily reduced.

<Embodiment 2>
The configuration of the network device according to the second embodiment of the present invention will be described with reference to FIG. In FIG. 5, not only the PoE that receives power from the LAN, but also a power connector 320 is provided on the fixed portion substrate 302 to enable operation with an AC / DC power source. Further, a PT (Pan-Tilt) control unit 260 for performing a pan / tilt operation is provided on the movable part substrate 202. In contrast to the PT controller 260, the tilt driving motor 440 is provided on the movable part side via the connector 280, whereas the pan driving motor 450 is provided on the fixed part side via the connector 270. .

  FIG. 6 is a block diagram of the fixed part substrate 302 according to the second embodiment. Here, a power connector 320 is added to the fixed part substrate 300 of FIG. The AC / DC power supplied from the power connector 320 via the signal lines 321 and 322 is rectified by the diode bridge 323 and supplied to the PoE and DC compatible insulated power supply unit 315. The insulated power supply unit 315 incorporates a diode OR circuit (not shown) for switching input from the diode bridges 316 and 317 on the PoE side and input from the diode bridge 323 on the power supply connector 320 side. The diode OR circuit switches between power control by PoE supply and power control by AC / DC supply according to the priority order.

  As in the first embodiment, the network communication signal system is connected to the LAN connector 330, the pulse transformer 340, the connector 350, the signal line 370, the connector 240, and the physical layer controller (PHY) 230, and the system itself does not change. In other words, the present invention is an invention that considers PoE, but is not related to the presence or absence of PoE, and is similarly established in an AC / DC supply system without PoE.

  As described above, according to the second embodiment, the same effect as that of the first embodiment can be obtained even in the configuration in which power is supplied by at least one of PoE and AC / DC.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

Claims (6)

A network device having a network interface,
A first substrate comprising a LAN connector and a pulse transformer;
A second substrate including a physical layer controller and a network processing unit,
The network device, wherein the pulse transformer included in the first substrate and the physical layer controller (PHY) included in the second substrate are connected by a connection cable. The first substrate further includes a power supply unit,
The network device according to claim 1, wherein power is supplied to the second substrate via the connection cable by the power supply unit included in the first substrate. The network device according to claim 2, wherein the power supply unit is a PoE power supply unit corresponding to PoE supplied from a network interface. The first substrate is disposed in a fixed part of the network device,
4. The network device according to claim 1, wherein the second substrate is disposed on a movable part of the network device. 5. The said movable part is further provided with the lens for imaging an image | video, the sensor which detects the image imaged with this lens, the pan mechanism and the tilt mechanism for changing an imaging direction. Network equipment. The movable part further includes a lens for capturing an image, a sensor for detecting an image captured by the lens, and a tilt mechanism for changing an imaging direction,
The network device according to claim 4, wherein the fixing unit further includes a pan mechanism for changing an imaging direction.

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