JPH0851671A - Data communication equipment for engine control - Google Patents

Abstract

PURPOSE:To provide a data communication equipment for engine control improved so as to simplify a communication equipment along with the simplification of a communication frame by utilizing a LAN system. CONSTITUTION:For the ignition devices 221 to 224 and fuel injection devices 231 to 234 of the respective cylinders (#1 to #4) of an engine 21, the communication equipments 241 to 244 are provided for the respective cylinders and ignition control data from an electronic control unit 25 for the engine control are transmitted from the communication equipment 26 through the transmission line 27 of the LAN system to the communication equipments 241 to 244. The transmitted communication frame is provided with the ID of the cylinder, the data A of energizing time DELTATA, the data B of a difference DELTATB between an ignition timing and an injection timing and the data C of fuel injection time. DELTATC and is transmitted from the communication equipment 26 while matched with the ignition time period. Then, an ignition timing is set at the time of completing the reception of the communication frame and ignition timing data are omitted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a LAN system which constitutes an engine control system set in a vehicle such as an automobile, and is particularly set in each cylinder of an engine from an electronic control unit for vehicle control. The present invention relates to a data communication device for controlling an engine that transmits a control command to an ignition means.

[0002]

2. Description of the Related Art A vehicle is equipped with a large number of electronically controlled devices and sensors, and information detected by the sensors is input to an electronic control unit composed of a microcomputer or the like. In this electronic control unit, control information for various control targets is calculated based on the detection signals from the sensors, and the detection information from the sensors and the control information from the electronic control unit are stored in the vehicle. Exchanged by multiplex communication using the set network. That is, data is exchanged between the master station, which is an electronic control unit, and a plurality of slave stations corresponding to the control targets and sensors by multiplex communication.

For example, when an engine mounted on this vehicle is to be electronically controlled using multiplex communication,
LAN (Local Area Network) for engine control in the vehicle
The system is configured to perform engine ignition control and fuel injection control using this LAN system.

Considering the case of executing the ignition control of the engine by using the multiplex communication as described above, such an ignition control controls the ignition timing and the energization time to the ignition coil. In order to control the ignition timing and the energization time to the ignition coil, two data, the ignition timing data and the energization time data calculated by the electronic control unit, are transferred from the master station composed of the electronic control unit to the slave stations corresponding to each cylinder. Ignition control is performed by processing the two data transmitted and transmitted by each slave station.

FIG. 5 shows an example of a conventional engine control device using a LAN system. An injector for ignition control from an electronic control unit (ECU) 11 for engine control and an injector corresponding to a fuel injection amount. A signal for controlling the injection time is sent to the transmission line 13 that constitutes the LAN system via the master station communication device 12. In addition, the ignition device 14 is provided for each cylinder (# 1 to # 4) of the engine.
1 to 144 and fuel injection devices 151 to 154 are respectively set, control commands from the slave station side communication devices 161 to 162 are given to the ignition devices 141 to 144, and the fuel injection devices 151 to 154 are respectively supplied. Is given a control command from the slave station communication devices 171-174.

Then, these slave station communication devices 161-164 are provided.
Control data for ignition control and fuel injection control from the master station communication device 12 is transmitted to each of 171 and 174 through the transmission line 13. In this case, the signals sent from the master station communication device 12 to the transmission path 13 are set for ignition control and fuel injection control, respectively, and their communication frames are also set correspondingly for ignition control and fuel injection control, respectively. It

In such an engine control device, ignition control data for each corresponding cylinder is transmitted from the master station communication device 12 to each of the slave station communication devices 161-164, and each of the communication devices 161-164 receives. By processing the received ignition control data, the ignition devices 141-144 of each cylinder are processed.
Direct ignition control. In performing such ignition control, particularly in the ignition timing control, highly accurate control with little time error and no malfunction is required. For this reason,
The communication format inevitably becomes complicated and the communication frame length becomes long. Further, in order to process such a complicated format, the communication control circuit in the communication device 12, 141-144 is also complicated, and the circuit scale is inevitably large.

Further, if the ignition control and the fuel injection control are performed using separate communication frames, the amount of communication on the transmission path increases, and a higher communication speed is required. Further, since the communication device is provided corresponding to each of the ignition control and the fuel injection control, the mounting is restricted.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is intended to ensure highly accurate ignition timing control with certainty and fuel. The communication frame including the injection control is sufficiently simplified to improve the communication efficiency on the transmission path, and the control circuit of the communication device can be simplified. Particularly, it is advantageous to be mounted on a vehicle. The present invention aims to provide a data communication device for controlling an engine.

[0010]

A data communication apparatus for controlling an engine according to the present invention is a LAN set in a vehicle.
In the system, ignition means and fuel injection means are set corresponding to each cylinder of an engine mounted on a vehicle, and communication means is set corresponding to each cylinder of the engine. Ignition control of the engine The fuel injection data together with the data is transmitted to each of the communication means of each cylinder and L
It is calculated and output by an electronic control unit connected via a transmission line that constitutes the AN system. Then, from this electronic control unit, to each of the communication means corresponding to each of the cylinders, a communication frame including ignition control data and fuel injection data of the cylinder is transmitted at a timing corresponding to the ignition timing of the cylinder. I am trying to do it.

Here, the electronic control unit transmits the ignition control data and the fuel injection data corresponding to the corresponding cylinder to the communication means corresponding to each of the cylinders. The communication frame is transmitted so that the ignition timing is set to the timing.

[0012]

In the data communication device for engine control constructed as described above, the ignition control data sent from the electronic control unit to the communication means of each cylinder does not include data for ignition timing control. . Then, in the communication means of each cylinder, when the reception of the communication frame including the ignition control data sent from the electronic control unit is determined to be the ignition timing of the corresponding cylinder, the reception completion timing of the ignition control data is determined. The ignition timing of each cylinder is set and controlled. Therefore, the ignition timing data is not included in the transmitted data, and therefore the communication frame length for this purpose is sufficiently short and simple. That is, the control of the ignition timing is directly performed in the electronic control unit, and its accuracy is easily maintained, and the reliability of the electronic control of the engine is secured. In this case, the LAN is simplified with simplification of the communication frame to be transmitted
The simplification of the system is achieved, and the mountability on the vehicle is also effectively improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a network that constitutes an engine control device. The engine 21 includes first to fourth parts.
The cylinders (# 1 to # 4) are provided, and the igniter, ignition coil, and
Ignition devices 221-224 consisting of spark plugs etc. are set,
Further, fuel injection devices 231 to 234 are set. Then, the communication devices 241 to 244, which are slave stations corresponding to the respective cylinders, are set, and, for example, based on the ignition control data and the fuel injection data received by the communication device 241, the ignition device 221 and Allow the fuel injector 231 to be controlled.

An electronic control unit (ECU) 25 for engine control is set for such an engine 21. Although not shown in the figure, the engine control unit 25 includes a throttle valve corresponding to the intake amount signal for detecting the operating state of the engine 21, the rotation speed signal, the oxygen concentration detection signal from the exhaust gas, and the depression amount of the accelerator pedal. A detection signal such as an opening signal is supplied, and the electronic control unit 25 calculates control data such as an ignition timing and a fuel injection amount suitable for the operating condition of the engine 21.

The ignition and fuel injection control data calculated by the engine control ECU 25 is transmitted via the master station communication device 26 in the form of a predetermined communication data frame to form a non-collision type LAN system. Sent to 27. The transmission path 27 is connected to slave station communication devices 241-244 which are set corresponding to the respective cylinders of the engine 21.

FIG. 2 shows one ignition device 22 taken out and shown. The primary winding 311 of the ignition coil 31 is grounded via an igniter 32 composed of a switching transistor, and an ignition signal is inputted to the primary winding 311. This transistor is turned on, and a current flows through the primary winding 311 of the ignition coil 31. The secondary winding 312 of the ignition coil 31 is connected to the spark plug 33.
Is connected to the primary winding 311 in response to the ignition signal.
The spark plug 13 is operated by the high voltage induced in the secondary winding 312 based on the current flowing through the spark plug 13.

Here, the case where the # 1 cylinder of the engine 21 is ignited will be described as an example. Based on signals from the sensors, the engine control unit 25 causes the ignition timing of this cylinder and the energization of the ignition device 221. The time ΔTA (data A) is calculated. Then, the engine control unit 25 sends the calculated data A to the communication device 26.
A command signal is output so as to be transmitted at the ignition timing of one cylinder. Communication device (master station) 26 that received this transmission command
Sends data on the transmission line 27 with data A attached to the communication frame having the ID of # 1 as shown in FIG.

When a predetermined communication frame is transmitted to the transmission line 27 in this way, the communication device 241 of the cylinder # 1 identifies the ID of this communication frame and receives this communication frame.
Then, when the reception is completed, the ignition signal for the ignition device 241 is turned on, and this ignition signal is turned off after the energization time (ΔTA) of the data A has elapsed. Based on this ignition signal, the ignition device of the # 1 cylinder is activated. The 241 spark plug is ignited.

In such ignition control, the time (ΔTD) until the ignition plug is ignited after the signal is transmitted from the communication device 26 is constant because it is transmitted by the non-destructive LAN, The engine control unit 25 sends the signal early in consideration of this time ΔTD.

Next, when injecting fuel into the # 1 cylinder, the engine control unit 25 calculates the fuel injection timing and injection time (injection amount) together with the ignition timing. Here, the time difference between the calculated fuel injection timing and the ignition time is set to ΔTB (data B), and the injection time is set to ΔTC.
(Data C). The data B and C together with the ignition control data of the data A are sent from the master station communication device 26 to the transmission line 27 in accordance with the ignition timing, and the communication device 241 which is the slave station of the # 1 cylinder receives the data from the # 1 cylinder. The data A, B, and C of the frame having the ID indicating the cylinder are received. The communication device 241 includes an ignition device 221 and a fuel injection device 231.
To the control signal.

In the slave station communication device 241, after the reception of the communication frame including the data A to C from the master station communication device 26 is completed, the fuel injection timing and the ignition timing are set as shown in FIG. The injection signal is turned on after the elapse of the time difference ΔTB of. Then, the injection signal is turned off after the injection time ΔTC set by the data C has elapsed. In this way, in the cylinder # 1 of the engine 21, both the ignition and the fuel injection are controlled by one communication frame having the ID of # 1.

In the engine control unit 25, if the # 1 cylinder is controlled in this way, then the communication device 243 of the # 3 cylinder transmits data for ignition control and fuel injection control for the cylinder # 3 ( Data A, B, C) are transmitted to execute ignition and fuel injection control of this cylinder. After that, # 4
The cylinders # 2 and # 2 are controlled sequentially, and the engine
21 control continues.

In the data communication device for controlling the engine, the engine control unit 25 controls the ignition timing.
It is executed by directly transmitting a predetermined communication frame according to the ignition timing. Therefore, it is not necessary to incorporate data for controlling ignition timing in the format of the communication frame to be transmitted. Therefore, the configuration of the communication format itself can be simplified and the communication frame length can be shortened.

Therefore, a communication device including a communication control circuit
241 to 244 and 26 do not need to process complicated ignition timing control data, so that the circuit scale can be reduced, and the communication device can be easily reduced in size. Since the fuel injection control can be executed together with the ignition control by one communication format, the communication amount on the transmission line 27 can be effectively reduced and the communication speed of the LAN system can be lowered. Furthermore, since the ignition control and the fuel injection control can be performed by one communication device, the number of communication devices mounted on the vehicle can be reduced.

Here, if the ignition control and the fuel injection control are constituted by separate communication systems, if there is a failure in the communication system, there is a possibility that only fuel will be injected without ignition. There is a risk that the engine may be hindered. However, in the device shown in the embodiment, the ignition control and the fuel injection control always function at the same time. Therefore, in a situation where the ignition control function is stopped,
The fuel injection control function is also stopped at the same time. Therefore, the fail safe function is also satisfied.

For data A, B, and C indicating ΔTA, ΔTB, and ΔTC, reference values are set in advance in the slave stations corresponding to the respective cylinders, and only the correction values are transmitted via the transmission line 27. If the master station and each slave station can be coded with a common code, the communication frame can be further simplified and the data frame length can be effectively shortened. Can be achieved.

In the above embodiment, the electronic control unit
One communication device 26 is set for 25, and the output data from the electronic control unit 25 is transmitted to one of the communication devices 241 to 244 of each cylinder (# 1 to # 4) of the engine 21 through one transmission path 27. I am trying to do it. However, as shown in Figure 4
The cylinders 1 to # 4 are divided into, for example, two groups, and the master station side communication devices 261 and 262 are set corresponding to the respective groups. Then, the communication device 261 communicates with the communication devices 241 and 242 of the first group via the first transmission line 271, and the communication device 262 communicates with the communication devices 24 of the second group.
It is also possible to make 3 and 244 communicate with each other via the second transmission line 272.

According to this structure, when one of the transmission lines constituting the LAN system fails, the ignition control of the cylinder corresponding to this transmission line and the fuel are transmitted via the other normal transmission lines. Since the injection control can be executed, engine stall can be effectively avoided,
The fail safe function is set.

Communication devices 241-244 for each cylinder of the engine 21
The connection structure for the ignition devices 221 to 224 and the fuel injection devices 231 to 234 of the corresponding cylinders is the communication device 241 of the cylinder # 1 in the embodiment shown in FIG.
From the # 1 cylinder ignition device 221 and fuel injection device 231
However, this does not mean that one cylinder is provided with one ignition coil independently, but the cycle phase of the engine is different for each of the two cylinders by 360 ° in crank angle. It is also possible to control ignition only by providing an ignition coil with an igniter and connecting the ignition signal line of the two-cylinder communication device to the ignition coil.

In the case of a 4-cylinder engine, instead of independent injection in which one fuel injection device is independently set in one cylinder, for example, one fuel injection device is set in two cylinders # 1 and # 3, Communication devices 241 and 243 for cylinders # 1 and # 3
The fuel injection signal line in the above is connected to this fuel injection device to control the fuel injection, and similarly, the fuel injection devices commonly set in the cylinders of # 2 and # 4 are connected to the communication devices 242 and 244 of these cylinders. I tried to connect the signal line from
It is also possible to execute two-group injection. In addition, 1
By setting one fuel injection device for one engine and connecting the signal lines for fuel injection control of the communication devices 241 to 244 corresponding to all the cylinders to this one fuel injection device, injection is performed for each rotation. It is also possible to provide them, and it is also possible to appropriately combine these.

[0031]

As described above, according to the data communication device for engine control according to the present invention, in the electronic control unit for engine control, the transmission timing of the operation data is set in accordance with the ignition timing, thereby performing the communication. The format structure can be simplified and the frame length can be shortened. In particular, since data processing for ignition timing control can be eliminated, it is possible to reduce the size and simplification of the size of the communication device and reduce the amount of communication on the transmission path. In particular, the number of communication devices mounted on the vehicle can be reduced, and the control of the ignition timing, which is particularly important in engine control, is executed with high accuracy and sufficient reliability.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating a data communication device for controlling an engine according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an ignition device used in the above embodiment.

FIG. 3 is a signal waveform diagram illustrating a control operation of the above embodiment.

FIG. 4 is a configuration diagram illustrating another embodiment of the present invention.

FIG. 5 is a configuration diagram illustrating a conventional device.

[Explanation of symbols]

21 ... Engine, 221-224 ... Ignition device, 231-234 ... Fuel injection device, 241-244, 26 Communication device, 25 ... Engine control unit, 27, 271, 272 ... Transmission line.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location F02D 41/36 A 45/00 374 Z 380 F02P 3/05 Z 5/15 H04L 12/40

Claims (5)

[Claims] 1. In a LAN system set in a vehicle, an ignition means and a fuel injection means set corresponding to each cylinder of an engine mounted in the vehicle, and a control command to the ignition means and the fuel injection means. give,
A slave station communication unit set corresponding to each cylinder of the engine, fuel injection data is calculated together with ignition control data including an ignition timing of the engine, and the communication unit of each cylinder and the LAN system are configured. And an electronic control unit including a master station communication means connected via a transmission line, from the master station communication means of the electronic control unit to each slave station communication means corresponding to each of the cylinders. A data communication device for engine control, wherein a communication frame composed of ignition control data and fuel injection data of the cylinder is transmitted at a timing corresponding to the ignition timing of the cylinder. 2. From the electronic control unit to each slave station communication means corresponding to each of the cylinders,
A communication frame including ignition control data and fuel injection data corresponding to the corresponding cylinder is transmitted, and the communication frame is transmitted so that the reception completion time of this communication frame is the timing corresponding to the ignition timing. The data communication device for controlling an engine according to claim 1. 3. The ignition control data is configured to include an energization time for an ignition coil, and the fuel injection data is configured to include fuel injection time data corresponding to a fuel injection timing and a fuel injection amount. Data communication device for engine control. 4. A LAN system set in a vehicle, wherein ignition timing corresponding to each cylinder of an engine mounted on the vehicle, ignition control data including energization time for ignition control, and fuel injection amount are included. One communication frame, which is composed of an electronic control unit to be calculated and output data from the electronic control unit, and which is composed of the ignition control data and fuel injection data including a fuel injection timing and a fuel injection amount, is used in the LAN system. A master station communication means for sending out to a transmission path that constitutes a cylinder, an ignition means and a fuel injection means set corresponding to each cylinder of the engine, and each cylinder corresponding to the ignition means and the fuel injection means. Set to, receiving a communication frame transmitted from the master station via the transmission path, respectively configuring a plurality of slave stations, Station communication means and slave station communication means of the same configuration, each slave station sends an ignition command to the ignition means of the corresponding cylinder when the reception of the communication frame for the corresponding cylinder is completed, A data communication device for engine control, wherein the fuel injection means controls the fuel injection within a time range based on the fuel injection data. 5. The communication means set corresponding to each cylinder of the engine is divided into a plurality of sets, and transmission lines from the electronic control unit are set corresponding to the divided areas, respectively. The data communication device for controlling an engine according to claim 1 or 4.