JPH0616616B2 - Multiplexer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field The present invention relates to a multiplex transmission device in an automobile.

(B) Summary Signals are transmitted and received between the instrument panel and the rear trunk room by optical multiplex transmission. Electrical multiplex transmission is performed between electrical components in the rear luggage compartment. Electrical multiplex transmission is performed between the multiplex transmission terminal in the instrument panel and nearby electrical equipment.

(C) Conventional technology and its problems Car electronics is making remarkable progress. The number of electronic devices in automobiles is increasing more and more. For this reason, the places where electronic devices are mounted are decreasing.

In addition, even existing electronic equipment is required to have a functional capability, and along with this, the volume of each equipment may increase.

These devices were originally installed near the instrument panel, but since the number of installation locations has gradually decreased and the space available has decreased, new luxury and large-scale devices have been installed in the trunk room. I have to do it.

In addition to the increase in the number and volume of electrical components, the size of the wire harness that connects the periphery of the driver's seat with these electrical components will become larger. The wire harness is passed through a slight path between the electric component and the driver's seat, but when the amount of the wire harness increases, the wire harness becomes thick and difficult to bend. If it is not bent, it cannot pass through a narrow path. The wire harness must be heated to make it easier to bend and then passed through narrow gaps and curves.

This alone hinders the assembling work, but if the wire harness becomes larger, the wire harness can no longer pass through.

If this happens, the vehicle will not be established.

Even so, enlargement of the wire harness makes the vehicle body heavy and is not desirable.

(C) It is an object of the present invention to simplify the purpose of the wire harness, significantly reduce the amount of the harness, simplify the work of assembling the wire harness, and reduce the weight of the vehicle body.

Therefore, optical multiplexing and electrical multiplexing transmission are used together.

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

(D) Structure The in-vehicle multiplex transmission device of the present invention will be described with reference to FIG.

Reference numeral 1 is a vehicle body and 2 is an engine. Others, lamps, windows,
The individual parts such as the door are not shown for simplicity.

Multiplex transmission terminal X on the instrument panel section 3
To provide.

Inside the rear trunk room 4, there are many electrical components. It is complicated to write a lot of electrical components.
Only B and B are shown.

Further, it is assumed that there is an electric component C near the instrument panel section 3. This is, for example, an audio switch control computer having SW5. In addition to this, a large number of electrical components are installed near the instrument panel unit 3, but these are not shown.

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 through an instrument panel switch group 13. An ignition key switch is present in these, but is not shown.

The branch power line 14 is input from the wire harness 16 to the multiplex transmission unit (MCU) 18 via the input protection circuit 15. The power line is divided and arranged at each part of the vehicle. Here, the subsequent illustration of the power line is omitted.

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

Many wire harnesses 16 are connected to the inputs of the multiplex transmission unit 18. Of course, there are two states of ON and OFF.

The power lines are separated and connected to each part of the car. Therefore, the information is taken out from the wire harness 16 through an appropriate interface. It is a signal of many electrical components.

This is a large number of parallel signals.

The multiplex transmission unit 18 performs parallel / serial conversion of these parallel signals into a series of serial signals.

The serial signal thus obtained passes through the synchronizing circuit 19 and is input to the LED driver 22 from the transmission signal line 20. Here, the power is appropriately amplified, and the LED (not shown) emits light according to the serial signal. The serial signal may be FSK-modulated or PWM-modulated. In this case, the modulated signal drives the LED.

The LED driver 22 drives the LED in the optical connector 23 according to the transmission signal. It is often on or off drive, but if you need to speed up the operation, turn it on.
Two levels can be set to correspond to digital signals.

The optical fibers 9 and 10 are the instrument panel section 3,
It is connected to the rear trunk room 4.

The optical fibers 9 and 10 may be any of a quartz glass fiber, a multi-component glass fiber and 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 9. A plug that holds the end of the optical fiber is held therein.

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

On the side of the rear trunk room 4, again, a multiplex transmission / reception circuit is provided.

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

The receiving circuit 27 amplifies the currents of PD and APD, a binarizing circuit that compares the current with a predetermined threshold value and converts it into a binary value of "1" and "0", and an appropriate voltage level. It is connected to an output circuit that fixes and lowers the impedance.

In the digital signal 42, these data are transmitted as serial data, and the serial / parallel conversion circuit 2
8, the data is converted into parallel data. The parallel data is a command signal to a plurality of electric components installed in the rear trunk room 4. This is sent to the micro computer 29. Alternatively, the serial data may be directly transmitted to the microcomputer 29. The micro computer 29 displays from the received signal, selects a channel, opens / closes a relay, and turns on / off electrical components. On the other hand, the serial data is transmitted from the other digital signal line 43,
After entering Jianxion 51 and the electric wire 47, enter another electric component B in the rear trunk room.

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

The 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, the electrical component B is an audio control computer. In this case, the tuner 49 becomes a load. The electric multiplex signal is transmitted from the electric wire 47 to the serial / parallel conversion circuit 5
Enter 0 data input Din. Here, it is converted into parallel data. Alternatively, the serial data may be directly connected to the microcomputer 50.

The content of the parallel data is arbitrary. For example, it includes FM and AM instructions, tuning data, and volume setting data.

Several data are generated about the status of the tuner 49.
This data is parallel digital or analog data. In the case of analog data, it is converted to digital data by A / D conversion. The serial / parallel conversion circuit 50 also has a reverse conversion function, and converts digital data from parallel to serial. Serial data is electric wire 48
Then, it enters the digital signal line 46 through the junction 51.

Now, the microcomputer 29 controls the electric components. On the contrary, the condition of the electrical components is micro computer 29
Is given to the serial / parallel conversion circuit 28 as parallel data. It also has an inverse transform function. Parallel data becomes serial data here.

The serial data is input to the multiplexer 30 via the digital signal line 44. The multiplexer 30 is 2
One serial data is received and made into one serial data. The composite serial data is recorded on the digital signal line 45.
And is given to the LED driver 31.

The LED driver 31 amplifies the digital signal, shapes it if necessary, and gives a drive current to the LED. LED (not shown)
Is turned on and off in the optical connector 32 in response to changes in the composite serial data. An optical multiplex signal is generated. This optical multiplexed signal enters the returning optical fiber 10 from the optical connector 33 and propagates therein.

The optical multiplexed signal that has passed through the optical fiber 10 is sent to the optical connector 3
4 and 35, photoelectric conversion is performed by the photodiode PD or APD. After it becomes a current signal, it is amplified and binarized in the receiving circuit 36. The binarized electric signal enters the synchronizing circuit 19 from the serial data signal line 21, and is further input to the multiplex transmission unit 18. Here, serial / parallel conversion is performed to form parallel data.

Parallel data includes various digital signals.

The parallel data includes the state data of the electric component controlled by the micro computer 29 and the data indicating the state of the tuner when the control electric component such as the audio control computer is present.

It is assumed that there is another electrical component C for operation near the instrument panel section 3. For example, a switch control computer for audio or the like. It has SW5 for input. It is a switch operated by the driver by hand. There are switches for tuning, volume, etc.

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

The serial / parallel conversion circuit 38 returns this to a parallel signal. This is the sum of the number of stations selected and the number of steps digitizing the volume. These data are input into the multiplex transmission unit 18 via the parallel signal line 37.

Parallel (audio) data is multiplexed transmission unit 1
At 8, the data is serially converted, and the optical fiber 9 is transmitted as a part of the optical multiplex signal. This data is photoelectrically converted,
An electric component B such as an audio control computer is reached through the digital signal lines 42 and 43 and the electric wire 47. Here, the audio equipment is controlled via the computer.

On the contrary, the data representing the state of the audio equipment is converted into serial data, and then electric multiplex transmission is performed on the electric wire 48.
The light is converted to light and the light is transmitted through the optical fiber 10. After this, it is photoelectrically converted and enters the multiplex transmission unit 18,
It becomes parallel data here. Further, the parallel / serial conversion circuit 38 converts the serial data into the electric wire 40.
LED in the SW that has been pushed to reach the electrical component C and is pushed
Lights up.

In this way, data is exchanged between the electrical components B and C corresponding to each other by propagating through the three multiplexed transmission lines of electrical multiplex, optical multiplex, and electrical multiplex.

In the case of a simpler transmission of a signal indicating ON / OFF of the load, it is easy to have. For example, signals between doors and brake pedal depression. This will be called a vehicle signal.

The load is controlled by the micro computer 29.

The switch operation of the switch group of the instrument panel section 3 generates a digital parallel signal, which is converted into serial data by the multiplex transmission unit 18. This is transmitted through the optical fiber 9 and reaches the receiving circuit of the rear trunk room 4 to become an electric signal. It is converted into parallel data by the parallel / serial conversion circuit 28 and used by the electrical component B through the microcomputer 29.

On the contrary, the state variable from the electric component B is digital data, but it is converted into serial data by the parallel / serial conversion circuit 28. This is transmitted in the returning optical fiber 10 as an optical multiplexed signal. It is photoelectrically converted and converted into parallel data by the multiplex transmission unit 18. this is,
This is data that represents the on / off of the actual load.

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

Thus, in the present invention, the multiplex transmission terminal X of the instrument panel section 3 and the rear trunk room 4 are
An optical transmission / reception circuit is provided for the electric component A and the both are communicated by optical multiplex transmission.

In addition, the electrical component C near the instrument panel section 3
And the multiplex transmission terminal X is
Send and receive data.

Also between the electrical equipment A and electrical equipment B in the rear trunk room,
Data is transmitted and received by electric multiplex transmission.

(E) Effectiveness (1) The wiring harness is simplified. The amount of wire harness is greatly reduced. The cost of the harness can be reduced.

(2) To simplify the work of assembling the wire harness.

(3) The weight of the vehicle body can be reduced.

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

[Brief description of drawings]

 FIG. 1 is a schematic configuration diagram of a multiplex transmission device of the present invention. A, B, C ... Electrical equipment X ... Multiplex transmission terminal 3 ... Instrument panel section 4 ... Rear trunk room 5 ... Multi-switch 9, 10 ... Optical fiber 11 ... Power supply circuit 15 ... Input Protection circuit 18 ... Multiplex transmission unit 29 ... Micro computer 49 ...

Front page continuation (72) Inventor Yasuhiro Nagasaka 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Yoshinobu Kobayashi 1-3-3 Shimaya, Konohana-ku, Osaka-shi Sumitomo Electric Industries, Ltd. Company Osaka Factory (72) Inventor Kazuo Hirano 1-3-3 Shimaya, Konohana-ku, Osaka City, Osaka Prefecture Sumitomo Electric Industries, Ltd. Osaka Factory (72) Inventor Toshihiro Toda 1-1, Shimaya, Konohana-ku, Osaka City, Osaka Prefecture No. 3 Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Futoshi Nishida 1-3-3 Shimaya, Konohana-ku, Osaka City, Osaka Prefecture Sumitomo Electric Industries Ltd. Osaka Works (72) Inventor Koji Urai Yokkaichi, Mie Prefecture Nishisuehiro-cho 1-14 Toyo Harness Co., Ltd. (56) Reference JP-A-60-60050 (JP, A)

Claims (2)

[Claims] 1. A multiplex transmission terminal (X) having an optical transmission / reception circuit is provided in an instrument panel section (3), and an optical transmission / reception circuit is provided in an electrical component (A) in the rear trunk room (4) that requests a large number of signals. Is provided to multiplex transmission terminals (X) and electrical equipment (A) in the rear trunk room to perform optical multiplex transmission of signals and request a plurality of digital data close to the instrument panel section (3). Between the electrical component (B) and the electrical component (A), which electrically multiplex transmit signals between the component (C) and the multiplex transmission terminal (X) and request a plurality of signals in the rear trunk room (4). A multiplex transmission device characterized in that signals are electrically multiplexed between the two. 2. An electric component (A) is a display screen control computer, an electric component (B) is an audio control computer, and an electric component (C) is an audio switch control computer. ) Item.