JPH0498925A - Communication equipment - Google Patents

Abstract

PURPOSE:To reduce power consumption by controlling a switching means based on a change in the input signal of an external equipment so as to control the supply of power to a communication equipment used for other node. CONSTITUTION:The communication equipment (ECU1) of a specific node is provided with a relay circuit 18 (switching means) switching power to a communication equipment used for other node, and an MPU 5 (switching control means) controls the relay circuit 18 based on a change in an input signal to a door lock/unlock operation switch 11 (external device) to control the supply of power to a communication equipment used for other node. Thus when no communication is implemented in a door multiplex transmission system for door lock required to be in operation when an ignition key is turned off, the drive of ECUs 2-4 is stopped to lower power consumption.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a communication device.

[Conventional technology]

BACKGROUND ART In recent years, due to the increase in functions and electronic devices in vehicles, the number of wiring in vehicles has increased rapidly, and a multiplex transmission system has become necessary.

[Problem to be solved by the invention]

However, in a multiplex transmission system, in order to realize one function, in addition to conventional wiring, it is necessary to operate a plurality of electronic devices that realize the communication function. Therefore, if multiplex transmission is used to implement a function that needs to operate when the IG main key (ignition key) is off, that is, when the generator is stopped, power will be supplied to each electronic device during this time. It is necessary to keep it. Therefore, in the entire system, the dark current increases significantly, placing a burden on the battery, and in the worst case, restarting becomes difficult.

An object of the present invention is to provide a communication device that can reduce power consumption.

[Means to solve the problem]

The present invention relates to a communication device used in a specific node among a plurality of nodes connected via a transmission path, which includes switching means for turning on and off power to the communication device used in other nodes, and an external The gist of the communication device is a switching control device that controls the switching device based on a change in an input signal of the device to control the supply of power to a communication device used in another node. .

[Effect]

The switching control means controls the switching means based on a change in an input signal from an external device to control the supply of power to a communication device used in another node. the result,
Driving is stopped when no communication is performed.

〔Example〕

An embodiment embodying the present invention will be described below with reference to the drawings. This embodiment is embodied in a vehicle door multiplex transmission system.

As shown in FIG. 1, in this system, electronic control units (hereinafter referred to as ECUs) 1 to 4 are provided for every four doors, forming respective nodes. A microprocessing unit (hereinafter referred to as MPU) 5 and a communication interface 6 are provided on the door on the driver's seat side. Further, communication ICs 7 to 9 are provided in the ECUs 2 to 4 provided in other doors.

Then, the communication interface 6 of ECU1 and ECU2
The communication ICs 7 to 4 are connected to each other via a communication path line IO as a transmission path, and the MPU 5 is connected to each communication IC via a communication interface 6 and a communication path line IO.
Can communicate with C7-9.

A door lock/unlock operation switch 11 and a door lock detection switch 12 as external devices are connected to the ECUI on the driver's side door, and signals from the switches 11 and 12 are input to the MPU 5 via an input interface 13. . Further, a lock/unlock solenoid 14 is connected to the ECUI on the driver's side door, and the MPU 5 drives the solenoid 14 via an output interface 15.

Furthermore, the ECU1 is provided with a power supply circuit 16, which converts the voltage of the battery 17 into a predetermined voltage to supply power to each circuit in the ECU1. Also, ECU
I is provided with a relay circuit 18 as a switching means, and the relay circuit 18 includes a relay contact 18a and a relay coil 18b. It is connected to the.

Additionally, the ECUs 2 to 4 include door lock detection switches 22 to 2.
4 is connected, and signals from the switches 22 to 24 are sent to communication ICs 7 to 9 via input interfaces 25 to 27.
is input to the ECUI via the communication path line 10.
It is sent to PU5. Then, the MPU 5 calculates and generates a command signal corresponding to each ECU based on the received signal.

Also, ECU2~4 has lock/unlock solenoid 2.
The communication ICs 7 to 9 receive command signals sent from the MPU 5 of the ECU1, and the same solenoids 28 to 30 are connected via the output interfaces 31 to 33.
30 is driven.

Next, the operation of the door multiplex transmission system configured as described above will be explained.

When the door lock/unlock operation switch 11 is operated to the door lock side and communication is required, the MPU 5 excites the relay coil 18b of the relay circuit 18, closes the relay contact 18a, and closes the power supply circuit 19 of the other ECUs 2 to 4. ~
21. By supplying this power, each ECU
2 to 4 become operational. Furthermore, the MPU 5 excites the lock/unlock solenoid 14 for a predetermined period of time to perform a locking operation, and also connects the communication ICs 7 to 14 via the communication path line IO to lock other doors.
Communicate with 9. As a result, each lock/unlock solenoid 28-30 is driven for a predetermined period of time to perform a locking operation.

Then, the MPU 5 detects the door lock on the driver's seat side based on the signal from the door lock detection switch 12, and also detects the locking of other doors based on the detection signal from each door lock detection switch 22 to 24 via the communication path line IO. is detected and the series of door lock operations is completed.

After that, when each ECU 2 to 4 no longer needs to operate, the MPU 5 deenergizes the relay coil 18b of the relay circuit 18, opens the relay contact 18a, and connects the other ECs.
Stop power supply to U2-4.

A similar operation is also performed when unlocking the door. That is, the door lock/unlock switch 11
When the is operated to the unlock side, the MPU 5 controls the relay circuit 18 to supply power to the power supply circuits 19 to 21 of each ECU 2 to 4, and drives the solenoids 14, 28 to 30 for a predetermined period of time to enter the unlocked state. At the same time, after confirming the completion of the operation using the signals from the door lock detection switches 12, 22 to 24, the relay circuit 18 is controlled and each ECU
The power supply to the power supply circuits 19 to 2■ of 2 to 4 is stopped.

In this way, in this embodiment, the communication device (
A relay circuit 18 (switching means) for turning on and off power to communication devices used in other nodes is provided in the ECUI), and an input signal to the door lock/unlock operation switch 11 (external device) is provided by the MPU 5 (switching control means). The relay circuit 18 is controlled based on the change in the power supply to the communication devices used in other nodes. As a result, in door multiple transmission systems for door locks that need to operate when the ignition key is off (that is, while the generator is stopped), conventionally, power is supplied to each electronic device during this time. However, in this embodiment, the driving of ECUs 2 to 4 is stopped when no communication is performed, reducing power consumption. becomes.

Note that this invention is not limited to the above embodiments,
For example, in addition to a vehicle door multiplex transmission system, it may also be used in a system that starts power supply to other nodes when a buzzard switch is turned on, and stops power supply when the buzzard switch is turned off. [Effect] As detailed above, according to the present invention, an excellent effect of reducing power consumption is exhibited.

[Brief explanation of drawings]

FIG. 1 is a system configuration diagram of an embodiment. 1 is an ECU, 5 is an MPU as a switching control means
, 10 is a communication path line as a transmission path, 11 is a door lock/unlock operation switch as an external device, 18
is a relay circuit as a switching means. Patent applicant Nippondenso Toyota Motor Corporation

Claims (1)

[Claims] 1. A communication device used in a specific node among a plurality of nodes connected via a transmission path, and switching that turns on and off power to the communication device used in other nodes. and switching control means for controlling the switching means based on a change in an input signal of an external device to control the supply of power to a communication device used in another node. Device.