JP2603261B2 - Multiplex transmission equipment for vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a multiplex transmission device for a vehicle.

(Prior Art) In vehicles, especially in recent automobiles, which are highly electronic,
Since the signal transmission lines are dedicated respectively, the number and length of the signal transmission wire harnesses tend to be extremely large. The most concentrated part of this wire harness is in the cowl box that is located above the dash panel that constitutes the front wall of the vehicle compartment and that has a closed cross section that extends in the left-right direction. That is, the number of switches and the like operated by the driver is large around the driver's seat, and the number of devices for giving various information to the driver is large. For this reason, the wire harness tends to concentrate from both the left and right directions of the vehicle body toward the driver's seat. The wire harness is disposed in a cowl box having a relatively large space and excellent strength from the viewpoint of preventing damage and increasing the efficiency of the arrangement space.

By the way, recently, as a form of signal transmission in a vehicle, in order to reduce the number and length of wire harnesses,
A multiplex transmission system in which a plurality of types of signals are transmitted by one transmission line has been receiving attention. An example of applying this multiplex transmission system to a vehicle is disclosed in
JP-A-179356 or JP-A-56-157644. The former publication discloses a multiplex transmission between a meter around a driver's seat and a junction box in a cowl side portion. Further, the latter publication discloses a configuration in which a transmission line for multiplex transmission and a power supply line are separated from each other.

(Problems to be Solved by the Invention) By the way, multiplex transmission has an advantage that the number and length of transmission lines can be reduced, but when one transmission line is disconnected or the like, this transmission line is used. The transmission and reception of a plurality of types of signals are all impossible. In particular, when constructing a multiplex transmission system in an environment where the use conditions are severe due to vibration or high heat, such as a vehicle, there is something that can sufficiently cope with the occurrence of abnormalities in the transmission line. desired.

The present invention has been made in view of the above circumstances, and multiplexes signal transmission and reception at a place where various signals are most frequently transmitted and received, and an abnormality occurs in a transmission line of the multiplex transmission. It is another object of the present invention to provide a vehicular multiplex transmission device having a backup function in such a case.

(Means and Actions for Solving the Problems) In order to achieve the above object, the present invention has the following configuration. That is, a first multiplex unit disposed on one side of the dash panel constituting the vehicle front wall, a second multiplex unit disposed on the other side of the dash panel, and a vicinity of the instrument panel. And a third multiplex unit for handling input / output signals for operations around the driver's seat, and a third multiplex unit disposed near the dash and extending in the left-right direction, connecting the first and second multiplex units. A first transmission line to be disposed in the vicinity of the dash panel, extending in the left-right direction through the cowl box, and connecting the first and second multiplex units in parallel with the first transmission line. And a second transmission line to which the third multiplex unit is connected while forming a closed loop in cooperation with the first transmission line.

As described above, according to the present invention, the signal wiring in this portion is significantly reduced by using a transmission line for multiplex transmission instead of an extremely large number of wire harnesses as a dedicated line conventionally disposed in the cowl boss. Can be simplified.

Further, since the transmission lines connecting the two multiplex units located on the left and right sides of the vehicle body are constituted by at least two first and second transmission lines forming a closed loop in cooperation with each other, one transmission line is provided. Even if one transmission line is disconnected, the other transmission line can transmit a signal in exactly the same way as when both transmission lines are normal.

Embodiment An embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, a vehicle A has an engine room 1, a vehicle room 2, and a trunk room 3 in order from the front to the rear. As shown in FIG. 2, a cowl box B having a closed cross section that extends long in the left-right direction is formed on the upper part of the dash panel 4 that separates the engine room 1 and the passenger compartment 2 from the cowl panel 5 as shown in FIG. I have. The portion of the cowl box B located on the vehicle cabin 2 side is covered by the instrument panel 6.

In the cowl box B, a first multiplex unit 11 is provided on the right side of the vehicle body, that is, on the driver's seat side where the handlebars 7 are provided (at a portion referred to as a right cowl side portion). The second multiplex unit 12 is disposed at a portion (referred to as a left cowl side portion). The two multiplex units 11 and 12 are connected by a first transmission line 13 and also by a second transmission line 14. The two transmission lines 13 and 14 are equivalent to each other in terms of signal transmission with respect to the two multiplex units 11 and 12, that is, form a closed loop in cooperation with each other. The first transmission line 13 is disposed in the cowl box B, while the second transmission line 14 is disposed as far away from the first transmission line 13 as possible, for example, in the instrument panel 6. . Thus, the advantage of keeping both transmission lines 13 and 14 separated from each other is preferable in preventing both transmission lines from being disconnected from each other in a forward collision, for example. Therefore, the second
The transmission line 14 is not limited to the inside of the instrument panel 6 but, for example, in a closed section formed at the lower part of the dash panel 4 (the lower part of the dash panel 4 has a closed cross section extending in the lateral direction of the vehicle body by a normal cross member. ) Can also be arranged.

In the embodiment, the first multiplexing unit 11 handles signals of a portion which has conventionally functioned as a junction box. In the embodiment, the second multiplexing unit 12 handles signals for a fully automatic air conditioner. Further, the second transmission line 12 is connected to other multiplex units 15 and 16 that handle input or output signals for various switches and devices around the driver's seat.

In the embodiment, further, other multiplex units 17 and 18 are provided also in front of and behind the vehicle body. Among the front and rear multiplex units 17 and 18, the front multiplex unit 17 handles signals for lamps such as headlamps and turn signals, and the rear multiplex unit 18 is a turn signal,
It handles audio signals in addition to backup lamps. The front multiplex unit 17 and the second multiplex unit 12 are connected by a third transmission line 19 for multiplex transmission, and the second multiplex unit 12 and the rear multiplex unit 18 are formed by a fourth transmission line 20. ing.

With the multiplex transmission system as described above, each of the multiplex units 11, 12, 15 to 18 is connected to the transmission lines 13, 19, 20 in a bus system, and Connected in a manner.

The method of signal processing by multiplex transmission as described above is a time slot method (time division method) in the embodiment. Therefore, time position setting (channel setting)
A master terminal for transmitting a reference pulse for transmission to the transmission line is used. In the embodiment, the master terminal is incorporated in the first multiplex unit.
Of course, each of the multiplex units 11, 12, 15 to 18 corresponds to the above-described signal processing system, and inputs signals from switches, sensors, and the like to the respective multiplex units or loads (equipment such as motors, solenoids, and audio). Process input / output signals to For example, in the case of the time slot method, when a switch operation of a fully automatic air conditioner is performed by a driver, an input signal accompanying this operation is transmitted to the transmission line 1 at the timing of a channel previously allocated by the multiplexing unit 15.
The multiplexing unit 12, which is output to 3, 14 and receives this output at the timing of the assigned channel, outputs a signal that causes the fully automatic air conditioner to operate in accordance with the above-described operation. Output to That is, the logic circuit sets the temperature and the outlet position according to the input operation signal, and controls the operation of the solenoid for temperature adjustment and the solenoid for changing the outlet position so as to be in the set state.

FIG. 3 shows another embodiment of the present invention, in which the same reference numerals are given to the same components as in the above embodiment, and the description thereof will be omitted. In the present embodiment, when a closed loop is formed by the first and second transmission lines 13 and 14, the number of connection couplers used is reduced as much as possible. That is, one end of each of the two transmission lines is directly connected to the first multiplex unit 11 (directly attached), and the other end of each of the two transmission lines is connected to the connection terminal 21 of the connection coupler 20.
a and 21b are connected, and the connection terminals 21a and 21b are connected to each other to form a closed loop. Then, each of the multiplexing units 12, 15, 16 is connected to the above-mentioned closed loop transmission line.

(Effects of the Invention) As apparent from the above description, the present invention has the following effects.

Wiring space in the instrument panel can be reduced.

That is, the first and second multiplex units are arranged on both sides of the dash panel to disperse the concentration of wiring from various mounted devices to the instrument panel, and to operate switches, devices and the like around the driver's seat. Input / output signal
Input / output to / from the second transmission line via the multiplex unit enables transmission / reception of signals between the multiplex units arranged in various parts of the vehicle. Equipment (eg air conditioner)
This eliminates the need for a cable for directly connecting to the multiplex unit that accommodates the, and simplifies the wiring in the instrument panel and saves space.

The disconnection performance of the multiplex transmission line is improved, and high reliability can be achieved.

That is, since the first multiplex unit is often configured to have a function of a junction box,
The first multiplex unit affects the operation of all multiplex units, and if a multiplex transmission line between the first multiplex unit and the second multiplex unit breaks, the multiplex unit provided on the other side of the dash panel is broken. Although the group may be affected, by forming a closed loop with the first and second transmission lines, even if any part of the closed loop transmission line is broken due to damage or the like, the first and second transmission lines are disconnected. Since the second multiplex units can transmit and receive signals through a path opposite to the disconnection point, the connection between the first multiplex unit and the second multiplex unit is maintained even when the disconnection occurs. Similarly, since the first and third multiplex units can maintain the connection through the path on the opposite side to the disconnection, the third multiplex unit for operating around the driver's seat even when the disconnection occurs It is possible to continue the operation by transmitting and receiving an input signal to the multiplexing unit of interest, that is improved versus breaking performance.

Since the second transmission line is disposed in the cowl box, and the third multiplex unit relating to the switch device is connected to the second transmission line, the third multiplex unit relating to the switch device is not formed in the cowl box without unnecessary holes. Can be connected.

[Brief description of the drawings]

 FIG. 1 is an overall system diagram showing one embodiment of the present invention. FIG. 2 is a sectional view taken along the line II-II of FIG. FIG. 3 is a main part system diagram showing another embodiment of the present invention. A: vehicle B: cowl box 1: engine room 2: vehicle compartment 4: dash panel 5: cowl panel 11: first multiplex unit 12: second multiplex unit 13: first transmission line 14: second transmission line

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-288637 (JP, A) JP-A-57-176493 (JP, A)

Claims (1)

(57) [Claims] 1. A first multiplex unit disposed on one side of a dash panel constituting a front wall of a vehicle cabin; a second multiplex unit disposed on another side of the dash panel; A third multiplex unit disposed near the ment panel and handling input / output signals for operation around the driver's seat; and the first and second multiplex units disposed near the dash and extended in the left-right direction. The first to connect each other
A transmission line, disposed in the vicinity of the dash panel and extending in the left-right direction through the cowl box, and connecting the first and second multiplex units in parallel with the first transmission line. And a second transmission line connected to the third multiplexing unit to form a closed loop in cooperation with one transmission line.