JPH0477360B2 - - Google Patents

Abstract

In this monitoring device for signal lamps (RT-LA, GE-LA, GN-LA) of a road traffic signal arrangement with a control device (STE) for switching (RT-LS, GE-LS, GN-LS) the signal lamps and with a signal security device (SSE), the lamp current (I) of the red signals (RT-LA) and the lamp voltages (U) of the green and yellow signals (GN-LA, GE-LA) are monitored for conflict-free signalling and the circuits are checked for absence of malfunction. For this purpose, at regular intervals the existing switched states of the signals are changed for a short period of time. The signal security device (SSE) evaluates these expected changes as check signals; failure of a check signal indicates a malfunction of the signal securìty device. The short period of time is kept here to such a length that there is no visible effect on the signals, e.g. one millisecond. With a control instruction (KB) of the control device (STE) switched-on signal lamps are momentarily switched off and switched off signal lamps are momentarily switched on. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention has a control device for the switching of a traffic light and also has a signal maintenance device which controls the traffic light current for red lights and for green and yellow lights. The present invention relates to a signal lamp monitoring device for a road traffic signal, which monitors the signal lamp voltage for the presence or absence of a disturbed signaling condition and checks the switching circuit for the presence or absence of a fault.

Prior Art In road traffic signals, incorrect control of the signals can lead to serious accidents. In this case, it is not enough to simply monitor whether the stop signal lights function as specified; the monitoring device itself must also operate completely reliably and must therefore be monitored. It is known to monitor the signal lamp current of a red signal lamp (no proceeding signal) or the signal lamp voltage of a green signal lamp (proceeding permission signal) or a yellow signal to detect a malfunction or an unauthorized activation of a signal lamp, for example a red signal lamp. In addition, the function of the road traffic signal is monitored by means of a signal maintenance device, for example to ensure that a direction of traffic that is allowed to proceed does not receive a permission signal for the direction of traffic opposite to that direction. is also publicly known. Therefore, the signal maintenance device has the role of detecting abnormalities that pose a traffic hazard and taking necessary measures when a light signal malfunctions. A prerequisite for this is that the signal integrity device is fully functional. Therefore, signal integrity devices are usually designed with fail-safe techniques. However, this requires considerable technical effort and expense.

OBJECT OF THE INVENTION The object of the invention is therefore to constantly monitor the functioning of a signal maintenance device in a road traffic signal without requiring high circuit engineering outlays.

DESCRIPTION OF THE INVENTION According to the invention, the problem is that the existing signal switching state is switched for a short time at regular time intervals, and the signal maintenance device evaluates this expected switching as a check signal. If a condition of non-generation of the check signal occurs, this condition is resolved by signaling the presence of an operational failure of the signal integrity device.

In order to monitor (check) the functionality of the signal safety device, "errors" are inserted for a very short period of time in a predetermined time sequence during operation, and this error is used to determine whether the device responds as specified or not. It will be checked. If this expected error occurs, it is known that there are no faults or errors in the signal safety matrix of the signal safety device; if no "error" occurs, even a faulty function is signaled.

Preferably, said short period of time is selected so that no visible influence on the signal occurs, for example the duration of this interruption may be one thousandth of a second (1 ms).

In the road traffic signal mentioned at the outset, the function check of the signal maintenance device can be carried out as follows: by means of a check command of the control device, the signal light which is in the switched-on state is switched off for a short time;
A signal lamp that has been shut off is turned on for a short period of time, causing a signal switching condition that continues to exist.
It was designed so that it could be switched or interrupted.

Further, according to an embodiment of the invention, in the case of a red light,
The signal light switch in the conductive state is closed or opened for a short time, and in the case of a green or yellow signal, the signal light switch in the non-conductive state is controlled to be conductive or closed for a short time.

The current pauses of the red traffic light and the voltage pulses of the yellow or green traffic light that are created in this way are used to check the reliable operating state of the signal maintenance system. These current pauses and voltage pulses are evaluated by an evaluation device to determine whether they occur as expected in a time-defined order in accordance with a signal integrity matrix for a pass/fail condition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The block diagram below shows a possible functional check circuit arrangement for a signal integrity system. The individual signal lights RT-LA, GE-LA, GN-LA are supplied with power via the supply voltage terminals marked UV and NULL (zero voltage).
At that time, the signal light switch RT is connected to each signal light current circuit.
-LS, GE-LS and GN-LS are provided. Each signal light switch is opened and closed by the control device STE using check commands RT-SB, GE-SB, and GN-SB. For traffic light monitoring, the traffic light current I is monitored in the red traffic light RT-LA and therefore the current sensor
The signal RT-SI is supplied to the signal maintenance device via the IS. For the green and yellow signals, the respective signal lamp voltage U is monitored by a voltage sensor US, and therefore
The GN-SI- and GE-SI signals are fed to a signal maintenance device SSE. According to the invention, a check command KB is supplied by the control device STE to the signal light switch LS in the active state, ie when a predetermined signal switching state persists.
The RT-KB-check command deactivates a red light that lasts for a short period of time, for example 1/1000th of a second. Yellow - and green lights GE - LA and GN
-LA is illuminated for a short time by check commands GE-KB and GN-KB. In this function control process, the signal maintenance device evaluates as a check signal whether an expected response to the short-term inserted "error" appears. However, if this check signal is not present, a malfunction of the signal maintenance device is detected and, depending on the occurrence of the malfunction, the road traffic signal is partially or completely shut down or switched to flashing yellow.

Effects of the Invention According to the present invention, in a road traffic signal, it is possible to constantly monitor the function of a signal maintenance device without requiring high circuit technology costs.

[Brief explanation of the drawing]

The figure is a configuration diagram showing the present invention. UV, NULL...Power supply voltage terminal, RT-LA,
GE-LA, GN-LA...Signal lights, STE...Control equipment, SSE...Signal maintenance equipment.

Claims (1)

[Claims] 1 RT-, GE-, GN for switching signal lights
- Has LA control device STE and also signal maintenance device
Has SSE, this signal maintenance device is a red light RT-LA
signal light current I and blue signal and yellow signal GN-,
In a signal lamp monitoring device for a road traffic signal, which monitors the GE-LA signal lamp voltage U for the presence or absence of a confused signal state and checks the switching circuit for the presence or absence of a fault, it is are switched for short periods at regular time intervals, and the signal integrity equipment SSE evaluates this expected switching as a check signal;
A signal lamp monitoring device for a road traffic signal, characterized in that when a check signal is not generated, this condition signals the existence of an operational failure of a signal maintenance device. 2. The signal lamp monitoring device for a road traffic signal according to claim 1, wherein the short time is selected to be, for example, 1/1000th of a second (1 ms) so as not to visually affect the signal. 3. The check command KB of the control device STE shuts off the signal lamp that is in the ON state for a short time.
The road traffic device according to claim 1 or 2, wherein an ongoing signal switching state is switched or interrupted by turning on a signal lamp that is in a cut-off state for a short time. Traffic light monitoring device. 4 In the case of a red signal RT-LA, the conducting signal light switch RT-LS is briefly closed or opened, and the green or yellow signal GN-LA or GE-
In the case of LA, the signal light switch GN− in the non-conducting state
A signal light monitoring device for a road traffic signal according to any one of claims 1 to 3, wherein the LS or GELS is controlled to be conductive or closed for a short time.