JPS6343835A - Trouble judging device for integral control system of automatic transmission and engine - Google Patents

Abstract

PURPOSE:To make any trouble in a communication wire properly judgeable, by suspending trouble judgment of the communication wire at a time when terminal voltage in a battery is low, in case of judging any trouble in various communication wires set up between an engine controlling device and an automatic transmission controlling device. CONSTITUTION:Information to be exchanged between a device (b) controlling an engine (a) and another device (d) controlling an automatic transmission (c) is transmitted via various communication wires (e). In the above-mentioned equipment, when trouble judgement of these communication wires (e) is performed, first whether terminal voltage of a battery (f) is low or not is detected. Next, when the terminal voltage of the battery (f) detected is low, execution of the trouble judgment of these communication wires (e) is suspended by a device (h). With this suspension, for example, a signal to be originally turned off becomes less than the threshold value of on-off because the terminal voltage of the battery (f) is low whereby it is judged to be an off level, therefore such a possibility that one to be judged as normality might be judged to be trouble in error is prevented from occurring.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a failure determination device for an integrated control system of an automatic transmission and an engine.

[Conventional technology]

Automatic transmissions for vehicles that are configured to selectively switch the engagement state of a frictional engagement device by operating a hydraulic control device to achieve one of a plurality of gears are already widely known. ing. Furthermore, in such automatic transmissions for vehicles, various integrated control devices for the engine and automatic transmission have been proposed that change the engine torque during gear shifting (for example, Japanese Patent Application No. 59-234466). Changing the engine torque when shifting reduces the amount of energy absorbed by each member of the automatic transmission or the frictional engagement device that brakes them.
? +' can be done. As a result, the shift can be completed in a short time and with a small shift shock, giving the driver a good shift feeling, and rfEta
The durability of the engagement device is improved and it becomes possible to use the engagement device. [Problems to be Solved by the Invention] However, when configuring such a system, it is difficult to control the control means for controlling the engine, the control means for controlling the automatic transmission, and the timing and change of engine torque change control. If the means for determining processing specifications such as ω are integrated, problems arise such as the capacity of the computer becomes large, resulting in high costs, and it is disadvantageous when installed in a vehicle with limited storage space. Further, there are cases where engine torque control is not required due to the grade of the vehicle or the size of the engine output, and an integrated type is disadvantageous when considering common use and versatility. From this point of view, several technologies have been developed in which these control means are distributed (for example, Japanese Patent Application No. 1055/1983).
43>. However, when the control means for controlling the engine and the control means for controlling the automatic transmission are configured separately in this way, it is necessary to communicate between the two control means in order to change the engine torque during gear shifting. Various communication lines are required for this purpose, and when such communication lines are provided, there is a problem that the communication lines may be disconnected or short-circuited. As a result, a situation arises in which, in the case of a shift in which engine torque change control should normally be performed, the engine torque change control cannot be properly executed. When such a situation occurs, the amount of energy absorbed by the frictional engagement device on the automatic transmission side increases, which impairs the durability of the frictional engagement device. Furthermore, the problem arises that the shift time becomes longer and the shift is not completed in the buffer area of the accumulator, resulting in a greater shift shock. This is because, on the automatic transmission side, gear shift tuning specifications such as oil pressure are set with the assumption that the engine torque will be reduced a predetermined number of times during the gear shift. Therefore, failures in these communication lines need to be determined early and without error.

[Purpose of the invention] The present invention has been made in view of such problems, and includes various methods for functioning engine torque change control when the engine control means and automatic transmission control means are configured separately. It is an object of the present invention to provide a failure determination device for an integrated control system of an automatic transmission and an engine, which can determine a failure of a communication line without error. [Means to solve the problem]

As summarized in FIG. 1, the present invention comprises: an engine control means for controlling an engine; an automatic transmission control means for controlling an automatic transmission; A failure determination device for an integrated automatic transmission and engine control system, which is equipped with various communication lines for transmitting information between the automatic transmission control means and the automatic transmission control means, detects whether or not the terminal voltage of a battery is low. The above object is achieved by comprising means for determining the failure of the communication line when the terminal voltage of the battery is low.

[Operation and effects of the invention]

In the present invention, when detecting a failure in a communication line, the battery terminal voltage is first detected, and when the battery terminal voltage is low, the failure determination is stopped. Therefore, for example, because the battery terminal voltage is low, a signal that should originally be at the ON level becomes less than the 0N-OFF vA value and is determined to be at the OFF level, and as a result, what should be determined to be normal may be determined to be faulty. On the other hand, it is possible to prevent a problem in which something that should be determined to be malfunctioning is determined to be normal. In a preferred embodiment of the present invention, whether or not the battery terminal voltage is low is determined by determining whether a predetermined time has elapsed since the ignition switch was turned on and the starter was turned on. be. By doing so, failure determination can be easily suspended during a period when the battery terminal voltage is unstable, without particularly providing a voltage generator or the like. Therefore, there is no possibility that an erroneous determination will be made due to instability of the battery terminal voltage. Furthermore, if the failure determination is performed after the predetermined time has elapsed, it is possible to prevent the signals for determining the failure of the communication line and the signals for executing the original control from interfering with each other. Moreover, it is possible to perform failure detection before starting operation.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 2 is an overall schematic diagram of an integrated control system for an engine and an automatic transmission to which the present invention is adopted. The engine 1 and automatic transmission 2 are well known. The engine control computer 7 controls the fuel injection amount at the injection valve 19 and the ignition timing at the distributor 20 of the engine 1, so that the engine output 19 corresponds to the accelerator opening and the engine rotational speed. Also automatic transmission TL
12 is equipped with a lock-up clutch 5 in its torque converter 4, and the automatic transmission control computer 8 controls the solenoid valves 81 to 53 (Sa is for engaging the lock-up clutch) of the hydraulic control device 3. As a result of changing the oil passage inside the vehicle, the engagement state of the lock-up clutch 5 and each friction engagement device is selectively changed, and a gear position corresponding to the vehicle speed and accelerator opening degree is obtained.
It is possible to perform so-called direct-coupling driving in which the lock-up clutch 50 is activated at a specific gear position. The engine control computer 7 includes the engine rotation speed detected by the crank angle sensor 9, and the air 70-sensor 10.
intake air amount by , intake air temperature by intake air amount sensor 11 , throttle opening by throttle sensor 12 ,
The vehicle speed from the vehicle speed sensor 13, the engine cooling water temperature from the engine water temperature sensor 14, the brake ON signal from the brake switch 15, the shift lever position signal from the shift position sensor 16, and the battery terminal voltage signal from the battery sensor 20 are input. The engine control computer 7 determines the fuel injection amount and ignition timing based on these signals. In addition, torque change transmission @ (including torque change timing signal information) by three communication linemen is also input in parallel to this engine control computer 7 from the automatic transmission control computer 8 side. Information on the timing and change amount of torque change control during gear shifting is taken in from the automatic transmission, and engine torque change control using retard control is executed during actual gear shifting. On the other hand, the automatic transmission control computer 8 receives various signals from the throttle sensor 12, vehicle speed sensor 13, engine water temperature sensor 14, brake switch 15, shift position sensor 16, etc., as well as signals from the pattern select switch 17 for driving with emphasis on fuel economy or Driving selection pattern such as driving with emphasis on power performance, overdrive switch 1
The electromagnetic valves 81 to 8 are operated so that a signal such as permission to shift to overdrive by 8 is input, and a gear stage and a lock-up state corresponding to the vehicle speed, accelerator opening, etc. are obtained.
3 is controlled ON-FF. In addition, the automatic transmission control computer 8 is inputted with a communication line (■) from the engine control computer 7 for communicating the retardation control status, indicating that the engine 1 is executing the retardation control and that the engine 1 is under the retardation control. It is now possible to determine whether regulations have been requested. That is, this communication line (2) is in a state (permission signal) of rapidly repeating ON-OFF, thereby informing the automatic transmission control computer 8 that the retard control can be executed. Further, by turning this into the OFF state (prohibition signal), it is communicated that the retard control should be prohibited. Further, by turning this ON state (execution signal), it is notified that the retard control is currently being executed. The failure determination of the communication lines T and (2) in the above-mentioned embodiment device is carried out as follows. When both communication lines ■ and ■ are normal: First, an OFF level signal is sent to all three engine torque change amount communication lines ■ from the automatic transmission control computer 8 to the engine control computer 7 for a predetermined period of time. Transmit only T2. When the engine control computer 7 determines that all the signals are at the OFF level, it determines that all of the communication lines (■) are not disconnected (non-faulty), and sends the 0N-OFF signal, which is the same as the permission signal, via the communication lines (■). A high-speed repetitive signal is transmitted to the automatic transmission control computer 8 for a predetermined period of time 13. In the automatic transmission control computer 8, this 0N-
By receiving a high-speed repeating signal of OFF for only 13 minutes, it can be recognized that both communication lines (2) and (2) are normal. Note that this predetermined time T3 is set to be longer than the time that is considered to take when torque change control is actually performed. If even one of the communication lines is broken: Even if all OFF level signals are sent from the automatic transmission control computer 8, the engine control computer 7
On the side, one of them is recognized as an ON level signal. When this ON level signal is received, the engine control computer 7 transmits an ON level signal, which is the same as the engine torque change execution signal, for a predetermined time period 13 via the communication line (2). The automatic transmission control computer 7 can thereby recognize that one of the signal line workers is out of order. When the communication line ■ is disconnected: No matter what information the engine control computer 7 sends, if the communication line ■ is disconnected, the automatic transmission control computer recognizes it as an ON level signal, which is the same as an execution signal. do. Therefore, the automatic transmission control computer 8 side investigates whether or not this ON level signal has been transmitted for the predetermined time period of 13 or more, and determines whether it is a signal reporting a disconnection in the communication linework or whether the communication line It is possible to distinguish and recognize whether the wire itself is disconnected or not. FIG. 3 shows a failure determination control flow in the apparatus of the above embodiment. This control flow starts when the ignition switch is turned on. First, in step 202, the value of flag F is determined. This flag F indicates that the starter motor has not been turned on yet when it is 1, and indicates that the predetermined time Tset has not yet passed since the starter motor was turned on when it is 2. It is. Since it is initially set to zero, the process advances to step 204. In step 204, it is determined whether the starter motor is turned on. Step 20 until it is turned ON
5, flag F is set to 1 and step 202.2
The process returns to 204 via 07. Starter motor is ON
At the point in time, the process advances to step 206 and timer t is started. In step 208, it is determined whether the timer t has reached a predetermined time TSet. If the predetermined time Tset has not yet been reached, the flag F is set to 2 in step 210, and the process returns to step 208 via steps 202 and 207. During this predetermined time TSe1, the ignition switch is ON and the starter motor is OFF.
The time is set at a time when the battery terminal voltage is considered to be stable after being set to N. When this predetermined time TSet has elapsed, step 212
Then, the center line failure determination described above is performed. Thereafter, in step 214, flag F is reset to zero, and this flow ends. This control flow is based on the assumption that the battery terminal voltage is normally higher than a predetermined value, and this control flow is based on the assumption that the battery terminal voltage is momentarily extremely unstable immediately after the starter motor is turned on. After waiting for a period of instability, that is, after the battery terminal voltage has recovered to a predetermined value or higher, a failure determination of the communication line is made. As a result, before the vehicle starts driving, it becomes possible to determine the failure of the communication line without interfering with signals for original control and without error. FIG. 4 shows a second embodiment of the invention. In this embodiment, it is determined in step 302 whether or not the battery terminal voltage is greater than or equal to a predetermined value, and whenever the battery terminal voltage is greater than or equal to the predetermined value, failure determination of the communication line is always performed (step 304 ). As a result, as long as the battery terminal voltage is in a stable state, failure determination of the communication line can be performed at any time, and determination can be made at any time when the communication line has failed. It goes without saying that when performing continuous failure determination in this way, failure determination should be done in a way that does not interfere with the output signal for failure determination and the output signal for executing the original control. Nor. In addition, in the above embodiment, an example was shown in which the present invention is applied to an integrated control device for an automatic transmission and an engine, which is intended to perform control to change engine torque during gear shifting. There is no limitation on what kind of control the transmission and engine perform together.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the gist of the present invention, FIG. 2 is a schematic block diagram showing the configuration of an integrated automatic transmission and engine control device to which an embodiment of the invention is adopted, and FIG. 3 is a block diagram showing the gist of the present invention. , a flowchart showing a control flow for failure determination used in the above device, and FIG. 4 is a flowchart showing another control flow. 7... Engine control computer (engine control means), 8... Automatic transmission control computer (automatic transmission control means), ■, ■... Communication line, ■... Battery terminal voltage, V set ...Predetermined value.

Claims (2)

[Claims] (1) An engine control means for controlling an engine, an automatic transmission control means for controlling an automatic transmission, which is configured separately from the engine control means, and communication between the engine control means and the automatic transmission control means. A failure determination device for an integrated control system of an automatic transmission and an engine, comprising: various communication lines for transmitting information; means for detecting whether a terminal voltage of a battery is low; A failure determination device for an integrated control system for an automatic transmission and an engine, comprising: means for occasionally stopping implementation of failure determination for the communication line. (2) Check whether the battery terminal voltage is low or not when the ignition switch is turned on and the starter motor is turned on.
A failure determination device for an integrated automatic transmission and engine control system according to claim 1, wherein the failure determination device detects based on whether a predetermined time has elapsed since the failure is determined to be N.