JPS61288637A - Multiplex transmission equipment - Google Patents

Abstract

PURPOSE:To decrease the quantity of wire harness by connecting an instrument panel and a rear trunk room around the driver's seat by optical multiplex transmission and connecting the instruments and nearby electric equipments by electric multiplex transmission. CONSTITUTION:Optical fibers 9, 10 connect the instrument panel section 3 and a rear trunk room 4 and reception circuit 27, 36 and LED drivers 22, 31 are fitted to both ends of the fibers 9, 10 via optical connectors 24, 25, 34, 33 for optical transmission. Then an input signal from an instrument panel switch group 13 gives a command signal to electric equipments A via a following order; the path of the wire harness 16, a multiplex transmission unit 18, the driver 22, the fiber 9, the circuit 27 and a CPU 29 or electric devices B via an electric wire 47. The state of the electric equipments B is given to the panel section 3 via the opposite path to the said signal conversely. Further, electric equipment C near the panel section 3 are subjected to signal transmission/ reception by electric multiplex transmission wires 40, 41.

Description

[Detailed description of the invention] (g) Technical field TECHNICAL FIELD This invention relates to a multiplex transmission device in a motor vehicle.

(B) Summary Signals are transmitted and received between the instrument panel and the interior of the rear trunk using optical multiplex transmission.

Electrical multiplex transmission is carried out between the electrical components in the rear trunk. Electrical multiplex transmission is performed between the multiplex transmission terminal in the instrument panel and nearby electrical equipment.

(ri) Conventional technology and its problems Car electronics is making remarkable progress. The number of electronic devices in automobiles is increasing. As a result, the number of places to install electronic devices is decreasing.

Further, even existing electronic devices are required to have improved functionality, and along with this, the volume of each device may become larger.

These devices were originally installed near the instrument panel, but as the number of installation locations gradually decreased and the space became less available, new high-end and large-scale devices were installed in the trunk compartment. I have no choice but to equip it.

In addition to the increase in the number and volume of electrical components, the wires connecting these electrical components to the area around the driver's seat also become larger. The wire harness is passed through a small path between the electrical components and the driver's seat, but as the amount of wire harness increases, it becomes thicker and becomes difficult to bend. If you don't bend it, you won't be able to get through narrow paths. Wire harnesses must be heated to make them easier to bend before being threaded through tight gags and curves.

This alone hinders the assembly work, but if the wire harness becomes even larger, it will no longer be possible to pass the wire harness through it and it will become unworkable.

If this happens, the vehicle will fail.

Even if this is not the case, the enlargement of the wire harness is not desirable because it increases the weight of the vehicle body.

(i) Purpose It is an object of the present invention to simplify the wire harness, to significantly reduce the amount of harness, to simplify the assembly work of the wire harness, and to reduce the weight of the vehicle.

For this reason, optical multiplexing and electrical multiplexing transmission are used together.

The instrument panel around the driver's seat and the rear trunk are connected via optical multiplex transmission. The instrument panel and nearby electrical equipment are connected via electrical multiplex transmission.

(Gradient configuration) The in-vehicle multiplex transmission device of the present invention will be explained with reference to FIG.

1 is the vehicle body, and 2 is the engine. Other individual parts such as lamps, windows, doors, etc. are not shown for simplicity.

Multiplex transmission terminal X is installed in instrument panel section 3.
will be established.

Inside the rear trunk compartment 4, there are many electrical components. It would be complicated to draw a large number of electrical components, so only A and B are illustrated.

Further, it is assumed that there is an electrical component C near the instrument panel section 3. For example, assume that this is an audio switch control computer and has sw5. In addition, many electrical components are installed near the instrument panel section 3, but these are omitted from display.

The power supply circuit 11 includes a battery, and is divided into a number of branch power lines 14 from a main power line 12 via an instrument panel switch group 13.

An ignition key switch is present among these, but is not shown.

The branch power line 14 passes through an input protection circuit 15 and is input from a wire harness 16 to a multiplex transmission unit (MCU) 18 . The power lines are separated and installed to each part of the road vehicle. Here, further illustration of the power lines is omitted.

Among these, some of the power line signals may be input to the multiplex transmission unit 18 as serial data via the multiplexer 17.

A number of wire harnesses 16 are connected to the input of the multiplex transmission unit 18 . Of course, there are two types of situations: on and off.

Power lines are separated and connected to each part of the car. Therefore, information is extracted from the wire harness 16 through a suitable interface. It is the name of many electrical equipment.

This is a large number of parallel signals.

The multiplex transmission unit 18 transmits these parallel signals to -
Parallel/serial conversion is performed into a serial signal.

The serial signal obtained in this way passes through the synchronization circuit 19 and is input to the LED driver 22 from the transmission signal line 20. Here, the power is appropriately amplified to cause an LED (not shown) to emit light in accordance with the serial signal. The serial signal may be further subjected to FSK modulation or PWM modulation. In this case, the LED is driven by the modulation signal.

The LED driver 22 drives the LED in the optical connector 23 according to the transmission signal. It is often driven in an on/off state, but if high-speed operation is required, it is also possible to set two levels in the on state and make it compatible with digital signals.

The optical fiber 9.10 connects to the intubation panel section 3,
It is connected to the rear trunk room 4.

The optical fiber 9.10 may be a quartz glass fiber, a multicomponent glass fiber or a plastic fiber. Further, either a step index or a graded index may be used.

Optical connectors 24 and 25 are attached to both ends of the optical fiber 90. A plug is held within it that supports the end of the optical fiber.

The optical connectors 23, 24, 25, and 26 can be easily attached and detached.

A multiple transmitting/receiving circuit is also provided on the side of the rear trunk compartment 4.

In the optical connector 26 connected to the optical fiber 9, there is a photodiode PD or an avalanche photodiode APD.
and receives optical signals. This is an optical multiplex signal.

The receiving circuit 27 includes a circuit that amplifies the current of the PD and APD, a binarization circuit that compares the current with a predetermined threshold value and converts it into binary values of "1" and "0", and a circuit that amplifies the current of the PD and APD, and a binarization circuit that converts the current into binary values of "1" and "0". It is now equipped with an output circuit that lowers the impedance.

In the digital signal 42, these data are transmitted as serial data and sent to the serial/parallel converter circuit 2.
8, it is converted into parallel data. The parallel data is a command signal to multiple electrical components installed in the four rear trunk compartments. This is sent to the microcomputer 29. Alternatively, the data may be sent to the microcomputer 29 as serial data. The microcomputer 29 displays and selects according to the received signal.
This: Opens and closes stations, and turns electrical equipment on and off. On the other hand, serial data is transmitted from another digital signal line 43.
It passes through the junction 51 and the electric wire 47 and enters other electrical equipment B in the rear trunk room.

Wires 47 and 48 are multiplex transmission lines. Here, a twisted pair wire is illustrated.

Electrical component B is not just a load that turns on and off. It is an electrical component for control that exchanges many signals.

For example, electrical component B is an audio control computer. In this case, the tuner 49 becomes a load. The electrical multiplexed signal is transmitted from the electric wire 47 to the serial/parallel conversion circuit 5
Enter 0's data human power Din.

Here, it is converted into parallel data. Alternatively, it may be connected to the microcomputer 50 for serial data processing.

The contents of the parallel data are arbitrary. For example, FM, A
It should include instructions for M, data for selecting a station, data for setting the volume, etc.

A plurality of data regarding the state of tuner 49 is generated.

This data may be parallel digital or analog data. In the case of analog data, it is A/D converted to digital data. The serial/parallel conversion circuit 50 also has an inverse conversion function and converts digital data from parallel to serial. Serial data is wire 48
The signal passes through the junction 51 and enters the digital signal line 46.

Now, the microcomputer 29 controls electrical components. The status of electrical components is determined by the microcomputer 29.
The data is then applied to the serial/parallel conversion circuit 28 as parallel data. It also has a reverse conversion function. Parallel data now becomes serial data.

Serial data is input to multiplexer 30 via digital signal line 44 . The multiplexer 30 has two
Receives two serial data and converts them into one serial data. Composite serial data, digital signal line 45
The signal is then provided to the LED driver 31.

The LED driver 31 amplifies the digital signal, shapes it if necessary, and provides LED K drive current.

An LED (not shown) is located inside the optical connector 32 and turns on and off in response to changes in the composite serial data. An optical multiplex signal is generated. This optical multiplex signal enters the return optical fiber 10 from the optical connector 33 and propagates therein.

The optical multiplexed signal passing through the optical fiber 10 is transferred to the optical connector 34.
．． 35, and is photoelectrically converted by a photodiode PD or APD. After becoming a current signal, the reception circuit 1iR3
6, it is amplified and binarized. The binarized electrical signal enters the synchronization circuit 19 from the serial data signal line 21 and is further input to the multiplex transmission unit 18. Here, it is serial/parallel converted to become parallel data.

Parallel data includes status data of electrical components controlled by various digital signal line microcomputers 29, and data indicating tuner status if there is an electrical component for control such as an audio control computer. , is included in this parallel date.

Assume that there is another electrical component C for operation near the instrument panel section 30. For example, an audio switch control computer. This has SW5 for input. This is a switch operated by the driver's hand. There are switches for tuning, volume, etc.

Although there are a plurality of pieces of these operation data, they are converted into serial data by the parallel/serial conversion circuit 54. This is transmitted through the electric wire 41 to the junction 39 of the instrument panel section 3.

The serial/parallel conversion circuit 38 converts this signal back into a tlf parallel signal. This is the sum of the number of stations selected and the number of steps in which the volume is digitized. These data are input into the multiplex transmission unit 18 via the parallel signal line 37.

Parallel (audio) data is transmitted through multiplex transmission unit 1
At step 8, the signal is serially converted and transmitted through optical fiber 9 as part of an optical multiplex signal. This data is photoelectrically converted and
The digital signal line 42, 43 and the electric wire 47 lead to an electrical component B such as an audio control computer. Here, the computer l) is used to control the audio equipment.

Conversely, data representing the status of the audio equipment is converted into serial data and then electrically multiplexed and transmitted through the wire 48.
The light is converted into light and then optically multiplexed and transmitted through the optical fiber 10. After this, it is photoelectrically converted and enters the multiplex transmission unit 18.
This becomes parallel data. Furthermore, the parallel/serial conversion circuit 38 converts the data into serial data, which is then converted to the electric wire 40.
is propagated to electrical component C, and the LED in the pressed SW
to light up.

In this way, data is exchanged between the corresponding electrical components BSC by propagating through three multiplex transmission lines: electrical multiplexing, optical multiplexing, and electrical multiplexing.

The simpler case of transmitting a signal indicating whether a load is on or off is quite simple. For example, a signal such as a door gap or a brake pedal depression. This will be called a vehicle signal.

The load is controlled by a microcomputer 29.

Switch operations of the switch group of the instrument panel section 3 generate digital parallel signals, which are converted into serial data by the multiplex transmission unit 18. This is transmitted through the optical fiber 9, reaches the receiving circuit in the rear trunk compartment 4, and becomes an electrical signal. The data is converted into parallel data by the parallel/serial conversion circuit 28, passed through the microcomputer 29, and used by the electrical component B.

On the other hand, the state variable from electrical component B is digital data, but is converted into serial data by the parallel/serial conversion circuit 28. This is transmitted in the return optical fiber 10 as an optical multiplex signal.

The signal is photoelectrically converted and converted into parallel data by the multiplex transmission unit 18. This is data that represents the actual on/off state of the load.

These data clearly indicate whether the corresponding load is on or off by turning on or off a group of lamps on the instrument panel.

In this way, the present invention specifically includes the multiplex transmission terminal X of the instrument panel section 3 and the rear trunk compartment 4.
An optical transmitter/receiver circuit is provided with the electrical component A, and the two are connected through optical multiplex transmission.

In fact, the electrical component C near the instrument panel section 3 and the multiplex transmission terminal X transmit and receive data by electrical multiplex transmission.

Also between electrical equipment A and electrical equipment B in the rear trunk compartment.
Data is sent and received using electrical multiplex transmission.

(Inertial effect (1) Wire harness is simplified. The amount of wire harness is significantly reduced. Harness conut" can be reduced.

(2) Easily assemble the wire harness.

(3) The weight per vehicle body can be reduced.

(4) A vehicle can be constructed even if it is equipped with a large number of electrical components.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a multiplex transmission device according to the present invention. A, B, C...Electrical equipment Human power protection circuit 18...Multiple transmission unit 29-゛・Microcomputer 49 Tuner inventor Yoshinobu Kobayashi Hirano Kazuindo 1) Hironishi Satoshi Nishi Takao Taisaifuji Yasuhiro Nagaita Koji Urai

Claims (2)

[Claims] (1) A multiplex transmission terminal Signals are optically multiplexed between electrical component A in the trunk room, and signals are electrically multiplexed between electrical component C that requests multiple digital data near instrument panel section 3 and multiplex transmission terminal X. A multiplex transmission device characterized in that signals are electrically multiplexed and transmitted between the electrical component B that transmits and requests a plurality of signals in the rear trunk room 4 and the electrical component A. (2) Electrical component A is a display screen control computer, electrical component B is an audio control computer, and electrical component C
The multiplex transmission apparatus according to claim (1), wherein is an audio switch control computer.