JPH0524574Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to an automatic transmission having an alarm item storage function capable of storing error codes detected by a self-diagnosis function.

(Prior Art) Conventional automatic transmissions are aimed exclusively at small passenger cars, and include a fluid coupling such as a torque converter between the engine and the planetary gear transmission, and use pressure oil as the control medium. A typical planetary gear type transmission is equipped with a gear position switching means.

In addition, when developing automatic transmission systems for large freight vehicles, etc., it is important to note that the number of vehicles produced is significantly smaller than that of passenger cars, so it is costly to design new expensive torque converters, etc. Since this is extremely disadvantageous in terms of the above, automatic transmission devices are being considered that use drive systems such as friction clutches and transmissions as they are, including existing production equipment.

Some of these automatic transmission devices have a self-diagnosis function that detects an abnormality in the device and lights up a lamp so that the abnormality can be visually recognized.

(Problems to be Solved by the Invention) However, there is a possibility that the abnormality detected by the conventional self-diagnosis function may become unclear if the abnormality is subsequently restored.

An object of the present invention is to provide an automatic transmission having an alarm item storage function that allows error codes detected by a self-diagnosis function to be stored and displayed sequentially later.

[Structure of the invention] (Means and effects for solving the problem) A control unit that controls the operation of an automatic transmission and has a self-diagnosis function, and an error detection function when the control unit detects an error by the self-diagnosis function. an alarm means for warning the occurrence of
and an error code switch that is operated when displaying an error code. An automatic transmission having a warning item storage function, characterized in that it includes means for sequentially displaying error codes stored in a storage section on a display section when a code switch is operated.

(Embodiment) An automatic transmission having a warning item storage function according to an embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 11 denotes a control unit that controls an automatic transmission (not shown) using a conventional drive system such as a friction clutch or a transmission. This control unit 11 is supplied with a voltage V0 via a battery B and a voltage V1 via a starter switch 12. Further, a CPU (central processing unit) 13 is provided within the automatic transmission 11, and this CPU
The voltage V0 is supplied to the standby power supply Vcc of No. 13 through a resistor R and a diode D1.
Further, the voltage V1 is sent to the power supply/reset circuit 14, which supplies a reset signal to the CPU 13, as well as a power supply Vcc and a standby power supply Vcc via the diode D2. Further, 14S is an error code display switch, and its operation signal CHK is input to the CPU 13.

Incidentally, the CPU 13 is provided with a FIFO (first-in, first-out) memory 15, as shown in FIG. The driving transistor Q1 is controlled by the CPU 13, and the pilot lamp P is turned on when a failure is detected by the self-diagnosis function.

Next, the operation of an embodiment of the present invention configured as described above will be explained. First, if an error is discovered by the self-diagnosis function while driving, the third
As shown in the figure, the pilot lamp P is turned on (step S11). Since the lamp P lights up in this way, the driver can be made aware of the occurrence of an error with certainty. Next, the error code of this error is stored in the memory 15 (step S12).
Then, recovery work (fail-sake processing) for this error, for example, processing to set the gear to neutral is performed (step S13), and when this fail-sake processing is completed, the pilot lamp 15 is turned off (step S15). In this way, when an error is discovered by the self-diagnosis function, the error code is sequentially stored in the memory 15. In this way, since errors detected during driving are stored in the memory 15 in the order in which they were detected as error codes, error information can be retained even if the error is resolved during driving.

Next, when the error code stored in the memory 15 is to be displayed, the error code display switch 14S is closed. As a result, the code display process shown in FIG. 4 is performed. First, memory 15
The error codes are read out in order of oldest to last, and the error codes are displayed on the pilot lamp P (step S21). Error code display switch 14
When operated, the error code stored in the memory 15 is displayed on the pilot lamp P, so that the failure situation can be known. Additionally, since the abnormal location is displayed as an error code, there is an advantage that it is easy to determine where the failure is. Furthermore, since the error code is displayed when the error code display switch 14 is operated, maintainability is excellent, and failure conditions can be detected even when the vehicle is stopped. This display continues until the error code display switch 14S is returned to its original state (step S22). When the error code display switch 14S is returned to its original state, the memory 15
The contents of are cleared and the process is terminated.

In this way, error codes discovered by the self-diagnosis function can be stored in the FIFO memory 15 and displayed later. By using the FIFO memory 15, error codes are displayed in the order in which they were detected, allowing you to accurately determine the status of failures even if multiple failures have occurred in the past, and easily identifying the latest failure. You can know.

Although the error code is displayed in the above embodiment, it may also be output to a printer.

[Effects of the invention] As detailed above, according to the invention, it is possible to make the driver reliably aware of the occurrence of an error, and it is possible to retain error information even if the error is resolved during driving. Since the abnormal location is displayed as an error code, it is possible to provide an automatic transmission having a storage function for alarm items that makes it easy to determine which part is malfunctioning.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the configuration of an automatic transmission having a storage function for alarm items according to an embodiment of the present invention, Fig. 2 is a diagram showing the configuration of a FIFO memory, and Figs. 3 and 4 are diagrams showing the same implementation. 3 is a flowchart showing an example operation. 11...Control unit, 12...Starter switch, 13...Starter switch, 14
...Power supply/reset circuit, 15...FIFO memory.

Claims (1)

[Scope of utility model registration request] a control unit that controls the operation of the automatic transmission and has a self-diagnosis function; an alarm means that warns of the occurrence of an error when the control unit detects an error through the self-diagnosis function;
and an error code switch that is operated when displaying an error code. 1. An automatic transmission having a warning item storage function, comprising means for sequentially displaying error codes stored in a storage section on a display section when a code switch is operated.