JPS62144204A - Diagnosis system for solenoid valve driving - Google Patents

Abstract

PURPOSE:To improve reliability of a control system by comparing the output signal applied to a solenoid valve driving circuit with a monitor signal by one of two controllers for detection of abnormality and at the same time inserting the short break time to the output signal for each fixed period. CONSTITUTION:A main controller 1 and a controller 2 for emergency are connected to a solenoid valve 3. Here a control part 11 of the controller 1 functions to insert a short break time (t) after the drive of a fixed time T. While a monitor wire supervisory circuit 210 is provided to a control part 21 of the controller 2 of a spare system. Thus the level of a monitor wire M led from a drive circuit 14 of the controller 1 is always monitored by a timer 211. Then the abnormality of drive system is decided if an ON level is kept for the time T or longer. Thus a warning message is sent out for detection of the abnormality of the drive system.

Description

[Detailed Description of the Invention] [Summary] In a control system using electromagnetic valves, in an electromagnetic valve driving method in which one electromagnetic valve is driven by at least two control devices, one of the control devices is , by comparing the output signal (D) to the electromagnetic valve drive circuit and the monitor signal (M) to detect an abnormality, and by inserting a short interruption period (1) in the output signal at regular intervals, The other control device monitors the monitor signal (M) from the drive circuit for the electric iff valve and detects that the OFF' level continues for a certain period of time (T) or more. This is designed to detect an abnormality in the driving conditions for the electromagnetic valve from the self-control device.

[Industrial application field]

The present invention relates to a diagnostic method when one electromagnetic valve is controlled by a plurality of control circuits in a control system using electromagnetic valves.

With recent advances in computer technology, computer control has become commonplace in fields such as the automobile industry. For example, many hydraulic valves used to control transmissions, clutches, brakes, etc. In terms of control, electromagnetic valves are increasingly being used instead of conventional mechanical controls.

As a result, there has been a growing demand for improved reliability in the control mechanism of the electromagnetic valve, and in particular, brake,
Regarding control mechanisms such as steering wheels, it is necessary to detect abnormalities in the control system at an early stage due to the seriousness of the effects when a failure occurs.

In general, a redundant control system is often adopted as a method to improve the reliability of the control system, but in this case, an abnormality in the standby system is detected early and, for example, a warning message is sent to prevent accidents. Therefore, an effective abnormality detection method for the standby system is required.

[Prior art and problems to be solved by the invention] FIG. 3 is a diagram explaining a conventional diagnostic method for a drive circuit for an electromagnetic valve, in which (a) shows the drive circuit for an electromagnetic valve, and (b) shows a diagnostic method for the drive circuit.

As is clear from this figure, the conventional diagnostic method for the electromagnetic valve is to compare the output signal (D) from the control circuit (not shown) for the drive circuit with the monitor signal (M). It was determining whether the drive circuit was normal or abnormal.

However, in this conventional method, a plurality of e.g.
When two control devices are driving one electromagnetic valve, there is no drive signal (output signal (D)) in the standby system, so it is not possible to diagnose the normality of the standby system in advance. There was a problem.

In view of the above conventional drawbacks, the present invention provides a method for diagnosing the normality of a standby system drive circuit when a plurality of control devices drive one electromagnetic valve in an active/standby mode. The purpose is to

[Means for solving problems]

FIG. 1 is a principle block diagram of a diagnostic method for an electromagnetic valve drive circuit according to the present invention.

In the present invention, the control device 1 includes a control section (
CTL) 11, a drive signal (output signal) D to the drive circuit 14 for the electromagnetic valve 3 and a monitor signal -
Diagnosis is performed by comparing the current and current values, and if the driving circuit is to continue to be driven for a certain period of time or more, a short interruption period (1) is inserted at specific time intervals.

The control device 2 transmits the above monitor signal i to a monitor line monitoring circuit (BT) 21 in a control unit (CTL) 21.
0 and the timer 211, the signal level of the monitor line (M) is constantly monitored, and if the signal level continues for a certain period of time or longer, for example, at a "low level", an abnormality is detected in the drive circuit 24 system on the control device 2 side. The configuration is configured to determine that.

[Effect]

That is, according to the present invention, in a control system using electromagnetic valves, in an electromagnetic valve driving method in which one electromagnetic valve is driven by at least two control devices,
One of the control devices outputs an output signal (D) to the electromagnetic valve drive circuit.

In addition to detecting abnormalities by comparing with the monitor signal (M),
By inserting a short interruption period (1) in the output signal at fixed time intervals, the other control device monitors the monitor signal (M) from the drive circuit for the electromagnetic valve, and As described above, for example, by detecting that the °on ° level continues, an abnormality in the driving conditions for the electromagnetic valve from the self-control device is detected. This has the effect of being able to detect a failure on the side in advance, thereby improving the reliability of the redundant control system for the electromagnetic valve.

〔Example〕 Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a diagram showing an embodiment of the present invention, in which (a) shows a specific circuit, and (b) shows a driving waveform according to the invention for an electromagnetic valve.

In this figure, a main control device (C/U) 1 is a control device that drives a solenoid valve 3 in normal times, and an emergency control device (C/U) 2 is a control device that drives the electromagnetic valve 3 in normal times. When the main control unit (C/U) 1 becomes abnormal, it functions to drive the electromagnetic valve 3 instead of the main control unit (C/U) 1.

First, in figure (a), the main control unit (C/U) ■
When driving the electromagnetic valve 3 for a long time, its control section (C
TL) In 11, after driving T for a certain period of time, as shown in Figure (b), a short interruption period is inserted.

On the other hand, in the standby system emergency control device (C/[1) 20 control unit (CTL) 21, the monitor line monitoring circuit 21
0 is set, and the level of the monitor line (M) from the drive circuit 14 of the main control unit (C/U) 1 (for example, "on" level) is constantly monitored by the timer 211, and the "on" level is When this continues for a certain period of time (T) or more, it is determined that there is an abnormality in the drive system from the emergency control unit (C/U) 2, and a warning message is sent by an alarm circuit (not shown).

In the embodiment shown in the figure, for example, if the connection with the electromagnetic valve 3 is broken midway, the monitor line monitoring circuit 21
The transistor at 0 becomes the ob state, and the timer 21
1, a high level signal will continue to be input, but if the high level signal is counted and it is detected that it continues for at least the above T time,
By configuring the alarm circuit to be activated as a timeout, it is possible to detect an abnormality in the drive system.

In this way, even if the main control unit (C/U) 1 is in operation, the emergency control unit (C/U) 2 is able to control the main control unit (C/U) 2 when the main control unit (C/U) 1 goes down. (C/U) In place of l, the above electromagnetic valve 3
It is possible to self-diagnose whether or not it can be driven.

In this way, in the present invention, one electromagnetic valve is
In a redundant control system in which at least two control devices are configured to perform control in a working/backup format, the working system has a mechanism for determining failures by comparing the sent signal and the monitor signal. The standby system is characterized in that an abnormality in the standby system can be detected for preventive maintenance by time-monitoring the monitor signal from the active system.

Although this embodiment has been described using an example in which one electromagnetic valve is driven by two control devices, one for active use and one for standby, it goes without saying that the present invention is not limited to two control devices. That's true.

〔Effect of the invention〕

As described above in detail, the electromagnetic valve diagnosis method of the present invention is a control system using electromagnetic valves, and is an electromagnetic valve drive method in which one electromagnetic valve is driven by at least two control devices. In the above, one of the control devices outputs an output signal (
D) and the monitor signal (M) to detect an abnormality, and by inserting a short interruption time (1) in the output signal at regular intervals, the other control device By monitoring the monitor signal (M) from the drive circuit for a certain period of time (T) or longer, for example, by detecting that the "on" level has continued, the self-control device can drive the electromagnetic valve. Since it is designed to detect abnormal conditions, a failure on the control device side of the standby system can be detected in advance, which has the effect of improving the reliability of the redundant control system for the electromagnetic valve. .

[Brief explanation of drawings]

FIG. 1 is a principle block diagram of a diagnostic method for an electromagnetic valve drive circuit according to the present invention. FIG. 2 is a diagram showing an embodiment of the present invention. FIG. 3 is a diagram explaining a diagnosis method for a conventional electromagnetic valve drive circuit. It is. In the drawings, 1 is the main control unit (C/U) or control unit. 11.21 is the control section 1 (CTL) 14.24 is the drive circuit. 2 is an emergency control device (C/U) or control device. 210 is a monitor line detection circuit (DET). 211 is a timer, 3 is a solenoid valve. are shown respectively. One of the 5 decoys of the agency is Eve J and Oh Shir; Zutei 2 Mouth (α) (b) Rod 3 Hard

Claims (1)

[Claims] A control system using electromagnetic valves, wherein one electromagnetic valve (3) is controlled by at least two control devices (1,
In the electromagnetic valve drive system driven by 2), any one control device (1 or 2) outputs an output signal (D) to the drive circuit (14 or 24) for the electromagnetic valve (3). , monitor signal (M), and determines an abnormality based on the comparison result output signal, and the other control device (2 or 1) controls one of the drive circuits ( By providing means (210) for time-monitoring the monitor signal (n) from the self-control device (2, or 1
) A diagnostic method for an electromagnetic valve drive circuit, which is characterized by determining an abnormality.