JPH01103568A - Switching direction input circuit for switch - Google Patents

Abstract

PURPOSE:To aim at miniaturization and cost reduction by connecting photocouplers, detecting each current of both positive and negative polarities, in series and moreover, inserting each photocoupler for diagnostic function of these photocouplers, as well as connecting diodes bypassing a heteropolar current, in parallel. CONSTITUTION:A basic circuit 5, detecting the polarity of a current, consists of photocouplers F1-F4 and diodes D1-D4. Among them, F2 and F3 are of the photocouplers for input use, and F1 and F4 are those for diagnosis of these photocouplers F2, F3. When the photocoupler F1 is turned to ON or OFF and a value f2 of the photocoupler F2 inputted each to ON or OFF is turned to 1 0, a switch is situated at the normal position side, likewise it is detected to be at the opposite side from a variation in an input value f3 of the photocoupler F3. In addition, the basic circuit 5 is set up in a parallel dual system, whereby a no-current state to be produced at the time of shifting the switch is discriminated from zero of double input being considered at trouble in the photocoupler..

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to inputting the switching direction of a railway switch into an electronic interlocking device, etc., in which two physical quantities are transmitted by the polarity of an electric current, to a computer. Can be used when fail-safe input is required.

<Conventional Technology> An interlocking device is provided as a control device that controls signaling equipment within a station to ensure the safety of train operation.

In order to prevent a dangerous situation from occurring due to a failure of the interlocking device, the device has a fail-safe configuration, but as a condition for this, it is necessary that the status of the field equipment be inputted without error. A point machine is also a type of field equipment, but since the switching direction is transmitted by the current polarity of the display line, it can perform three operations depending on the state of positive polarity, negative polarity, and no current. It is manually operated using a switch indicator relay (KR), which is a signal relay for when the position is taken.

Currently, the relay interlocking device is being replaced by an electronic interlocking device using a computer, but the switching direction of the switch is still determined by reading the KR's normal position and opposite position contacts from the input circuit. ing.

<Problem to be solved by the invention> In the electronic interlocking device, the logic part has been replaced with a computer and the size has been significantly reduced compared to the conventional relay interlocking device, but the signal relay remains in the interface part.
- This was considered a problem when trying to make the layer smaller and more economical.

However, if an attempt was made to develop an electronic circuit that could replace the three-position KH and satisfy fail-safe properties, the scale of the circuit would increase, making it difficult to put it into practical use.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a simple circuit that can be directly connected to a conventional single display line, has the same function as KR, and has fail-safe properties. It is an object.

Means for Solving the Problems> For this reason, the present invention connects photocouplers in series to detect a positive current and a negative current, respectively.
Furthermore, diagnostic photocouplers were also inserted to diagnose the functions of these photocouplers. A basic ladder-shaped circuit was constructed by connecting diodes in parallel to these photocouplers to bypass currents of different polarity.

In addition, in order to distinguish between the no-current state that occurs when changing a point machine and the zero power of both people that may occur when a photocoupler fails, the basic circuit described above is arranged in a parallel dual system, and software is used to It is now possible to determine whether or not there is a circuit failure.

As a result, the status of a point machine can be directly input into a computer without error using a simple circuit, and even if a failure occurs in a manual circuit such as a photocoupler or diode, it will not be input as an incorrect input value. It can also be prevented from happening.

<Example> Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an embodiment of the present invention, and FIG. 2 is a circuit configuration diagram of the present invention.

In Figure 1, 1 is the circuit part of the present invention, 2 is the switch machine, 3 is the computer part to which the circuit of the present invention is interfaced, and 4 is the display line of the switch machine. show. Depending on the switching direction of the switch 2, a direct current of positive polarity or negative polarity flows through the display line 4, but the circuit l of the present invention
The direction is reliably input to the computer 3 using .

Next, the details of the circuit will be explained. In Figure 2, 5 is a basic circuit that detects the polarity of the current, including a photocoupler FLF2,
It consists of F3, Fl and diodes DL D2, D3, and D4. Among these, F2 and F3 are photocouplers for manual operation, while Fl and Fl are for switching current and diagnosing the photocouplers F2 and F3.

Suppose now that the point machine is changing to the localization direction, and a positive current is flowing through the display line 4.

At this time, if photocoupler F1 is on, the current will be F1→
Since the flow passes through the path F2→D3→D4, the human power value f2 of F2 taken in by the computer is 1.

Furthermore, if the photocoupler Fl is turned off, the path is cut off, so the human power value f2 becomes 0. Therefore, when the photocoupler Fl is turned on and off and the value f2 of the photocoupler F2 input for each becomes (1→0), it is determined that the point machine is on the localization side. At this time, the human power value f3 of the opposing photocoupler F3 takes (0-0). Furthermore, if the photocoupler F1 or F2 is out of order, the input value f2 will be (0-4-0) or (l
→1), but it will not be mistakenly interpreted as a conversion to the opposite side.

Next, we will discuss the case where the switch machine is turned to the opposite side. In this case, a current of negative polarity is flowing, and the current passes through a path of F4→F3→D2→D1. Therefore, it is possible to correctly detect the reversal side change from the change in the input value f3 of F3 using a similar method.

By the way, when switching a switch, the display line is cut off and no current of either polarity flows. Therefore, at this time,
Even if the circuit is normal, the human power values f2 and F3 are both (0
→0), which corresponds to one of the human cover patterns that can occur in the case of element failure, and is indistinguishable. Therefore, in the present invention, the above basic circuits are arranged in parallel as a dual system. When both human power values of the two basic circuits are (0→0), it is determined that the switch is being changed (the display line is cut off). On the other hand, from one basic circuit (l→
If the pattern 0) is input and it is detected that the pattern is localized or inverted, it is determined that a failure has occurred in the corresponding part of the other basic circuit. Of course, if the input cover turn becomes (l→l), it can be unconditionally determined that the circuit has failed.

<Effects of the Invention> As described above, according to the circuit of the present invention, information such as the position and reverse position information of a point machine can be directly input into a computer without error and without going through a signal relay or the like. For,
It can be used as an input means for computer systems that require fail-safe properties, such as electronic interlocking devices. As a result, the effects are significant, such as miniaturization of the device and cost reduction. Furthermore, even if a failure occurs in the circuit itself of the present invention, not only will information not be input erroneously, but the failure can be detected on the computer side while maintaining the functionality of the circuit, so it can be expected to improve maintainability.

The circuit of the present invention can be widely used not only as an input circuit for display lines of switch machines in railway signals, but also as an input circuit for equipment that outputs physical quantities by changing the polarity of direct current. It can contribute to the development of microelectronics in fields that require high performance.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment using the present invention, and FIG. 2 is a configuration diagram showing a circuit of the present invention. l...Circuit part of the present invention 2...Switch machine 3...
・Calculator 4...Display line 5...Basic circuit F
LF2, F3, F4...Photo coupler DLD2, D
3, D4...Diode F2...Input value of F2 f3...Input value of F3 Figure 1 Figure 2

Claims (1)

[Claims] In a circuit that detects the direction of current in the display line that indicates the switching direction of a switch, there are a photocoupler for detecting current in the forward direction, a photocoupler provided to switch this current, and a photocoupler for the reverse direction. Two sets of basic circuits are constructed by connecting in series a positive direction current detection circuit in which two diodes are arranged in a trapezoid shape to bypass the current, and a negative direction current detection circuit created in the same way. A point machine switching direction input circuit characterized in that by preparing and connecting in parallel to a point machine display line, input can be made directly to an electronic interlocking device without using a relay.