JPS6180913A - Operation time element circuit - Google Patents

Abstract

PURPOSE:To obtain an operation time element circuit high in accuracy and fail-safe property by starting simultaneously a digital time element circuit and an analog time element circuit, and determining an operation time element by AND of time element outputs of the two circuits. CONSTITUTION:When a contact 2 is turned on at the time t0, an analog time element circuit A and a digital time element circuit B start its operation, and in the circuit A, the (a) point potential rises by a time constant determined by a resistance R4 and a capacitor C4, and reaches a launch voltage V1 of a time element relay 6 at the time t1. On the other hand, in the circuit B, a clock from an oscillating circuit 3 is counted by a counter 4, and when it reaches a prescribed value, a pulse P1 is supplied to a gate G of a switch element 5 at the time t2 which is after the time t1. When the relay is operated by a single time element output of the circuit B, it is feared that the relay is operated by a wrong output pulse P2 within a prescribed time, but since the relay 6 becomes an operating state by AND of the circuit A and B, a circuit high in fail-safe property is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates primarily to an operating element circuit used for railway signal systems.

PRIOR ART This type of elemental circuit during operation is characterized by its failure or malfunction.
Since this can directly lead to serious accidents such as personal injury, it is necessary to satisfy fail-safe properties and be highly reliable. Conventional circuits of this kind during operation are as follows:
Various types have been proposed, but they can be broadly divided into digital types and analog types. The digital operating time element circuit determines the operating time element by counting the basic clock. FIG. 4 is a diagram showing the general circuit configuration of a conventional digital operation element circuit. When the condition input contact 2 is closed, power from the DC power supply 1 is input to the oscillation circuit 3 and the counter 4 through this contact 2. , start working.

Then, the counter 4 counts the basic clock given from the oscillation circuit 3 to 41, and when the counted value reaches a predetermined value, a time element output is given from the counter 4 to the switch element 5, and the switch element 5 is turned on. . As a result, the time element relay 6 is raised at an operating time element dependent on the count value of the counter 4.

Next, FIG. 5 is a diagram showing the general circuit configuration of a conventional analog operating element circuit. When the condition input contact 2 is closed, the capacitor C1 is charged by the DC voltage of the DC power supply l through the resistor R1. , when the charging voltage Vc of the capacitor C1 reaches the peak point voltage of the unijunction transistor Q1, the unijunction transistor Q1 becomes conductive and a voltage is generated across the base resistor R3, and this voltage triggers the switch element 5. When the power is turned on, the element relay 6 is lifted up. Therefore, the operating time of relay 6 is determined depending on the time constant of resistor R1 and capacitor C1.

Problems with the Prior Art Among the conventional operating time element circuits mentioned above, the digital operating time element circuit determines the operating time element by counting the basic clock, so the operating time element can be determined with relatively high precision. , it has advantages such as a high degree of freedom in setting time elements, a wide range, and easy miniaturization. but,
There are disadvantages such as the circuit becomes complicated and lacks simplicity, and ensuring fail-safety is not always easy.

On the other hand, analog time element circuits accumulate charge in the time constant circuit,
Since the operating time element is determined based on the discharge, it has advantages and disadvantages that are completely opposite to those of the digital type. In other words, it has advantages such as a relatively simple circuit configuration and easy fail-safety, but it is inferior to the digital type in terms of accuracy, degree of freedom, range, etc. of timeme setting. There is a risk that time element fluctuations may occur due to changes over time.

Purpose of the invention The present invention solves the above-mentioned conventional problems.

It is an object of the present invention to provide a highly reliable operating element circuit which has high fail-safe properties, can determine operating elements with high precision, has a high degree of freedom in setting operating elements, and can have a wide range.

In order to achieve the configuration and object of the present invention, the present invention provides an operation element circuit in which an operation element is determined based on the time when a condition is input.
A digital time element circuit that starts generation of a basic clock and a counting operation by inputting the condition described in iii, and outputs a time element determined by the count value; and a digital time element circuit that starts a time constant charging operation by inputting the condition and outputs a time element determined by the time constant. and an analog time element circuit, and the operating time element is determined by the AND of the time element outputs of the two time element circuits.

Embodiment FIG. 1 is an electrical circuit diagram of an operating time element circuit according to the present invention. In FIG. 0, A is an analog time element circuit, and B is a digital time element circuit. Similar to the conventional example shown in FIG. 4, the digital time element circuit B counts the oscillation circuit 3 that generates the basic clock and the basic tarock of this oscillation circuit 3, and starts counting when a predetermined count value is reached. It is configured with a counter 4 that generates an elementary output. In this embodiment, the oscillation circuit 3 and the counter 4 are connected to the DC power source 1 through the condition input contact 2.
The circuit is connected between the condition input lines (a) and (b) connected to the condition input lines (a) and (b), and is operated by the DC voltage applied through the condition input lines (a) and (b). The counting time element output of counter 4 is on the condition input lines (a) and (b)
A switch element 5 such as a thyristor inserted and connected in series to
is input to gate G of.

The analog time element circuit A includes a resistor R4 inserted and connected in series to the condition input line (a) or (b), and a capacitor C4 connected between one end a of this resistor R4 and the condition input line (b). Equipped with a time constant circuit. Rs.
is the discharge resistance. The connection point a between the resistor R4 and the capacitor C4 is the output end of the analog time element circuit A,
It is connected in series to the relay 6 and the switch element 5 through a diode D1 for blocking backflow. 61 and 62 are contacts that close when the time relay 6 is lifted up, the contact 61 is provided in parallel with the series circuit of the resistor R4 and the diode D1, and the contact 62 is connected in series with the discharging resistor R5 and with the capacitor C4. connected in parallel.

Next, the operation of the operating element circuit shown in FIG. 1 will be explained with reference to the 7-ken diagram in FIG.

First, as shown in Fig. 2 (A), when condition input terminal 2 is closed at to and a condition is input, then analog time element circuit A and digital time element circuit B start operating from this time to. . In analog time element circuit A, as shown in FIG. 2(B), the potential at point a, which is the charging voltage of capacitor C4, increases by E according to the time constant determined by resistor R4 and capacitor C4, and when one condition is input, to At time t1, which is delayed by time td1, the voltage reaching the voltage v1 of the time element relay 6 is reached.

On the other hand, in the digital time element circuit B, the oscillation circuit 3 generates a basic clock at the same time as the condition is input, and the counter 4 counts the basic clock. When the count value in the counter 4 reaches a predetermined value at time t2, which is delayed by time td2 from the time to when the condition is input, the counter 4 sends a signal to the gate G of the switch element 5 as shown in FIG. 2(C). A pulse P1 of the counting time element tdz is given.

Here, the time element relay 6 is in a state in which the potential at point a by the analog time element circuit A rises above its rise voltage 71, and the switch element 5 can be turned on by the output from the digital time element circuit B. To be kidnapped on condition that something is done. That is,
Since the time element relay 6 operates by the AND of the time element outputs of the analog time element circuit A and the digital time element circuit B, the operating time element is determined by the AND of the time element outputs of both time element circuits A and B. 0 Normally, time t1, when the potential at point a of analog time element circuit A reaches the voltage ■1 of time element relay 6, is more temporal than time t2, when pulse P1 is output from digital time element circuit B. It is set to be as fast as possible. Therefore, at 12 o'clock when the pulse PL is output from the digital time element circuit B, the potential at point a of the analog time element circuit A has already reached the time element relay pick-up voltage ■1, as shown in FIG. 2(B). Ori,
At the same time as the switch element 5 is turned on at time t2, the 1 hour element relay 6 is lifted up, and the counting time element td of the digital time element circuit B is turned on.
An operating element Td equal to z is obtained. In this way, in the normal operating state, the operating time element Td is determined by the counting time element tdz of the highly accurate digital time element circuit B, so the operating time element Td can be set with high precision.

Moreover, unlike the conventional method in which the digital time element circuit B is provided independently to determine the operating time element, the time element output of the digital time element circuit B and the time element output of the analog time element circuit A are ANDed. Since the operating time element Td is determined by
For example, as shown in FIG. 2(C), if an error pulse P2 is generated from the digital time element circuit B, it means that the potential at point a of the analog time element circuit A is the voltage Vl of the time element relay 6.
Before reaching , the time element relay 6 will not be lifted, so
There is no possibility of outputting an erroneous operating time element.In other words, in digital mode, the abnormal operation of the lead circuit B can be compensated for by the analog time element circuit A.3On the contrary, due to the abnormal operation of the analog time element circuit A, Even if the point a reaches the time element relay pickup voltage v1 earlier than the predetermined time element, if there is no abnormality in the time element output of the pulse PL from the digital time element circuit B, the operating time element Td will still be , is determined by the counting time element td2 of the digital time element circuit B, and does not cause any problem.

In addition, if a circuit failure occurs in either the analog time element circuit A or the digital time element circuit B, the time element relay 6 will not be lifted up and the operating time element Td will be extended, so it is fail-safe. can be secured.

When the time element relay 6 is lifted up as described above, its contact 61 closes and the time element relay 6 is self-held through this contact 61. Furthermore, when the contact 62 closes, the charge accumulated in the capacitor C4 is discharged through the resistor R5, thereby preparing for the next operation. Then, when the condition input contact 2 opens at time t3 and the power supply is cut off, the time element relay 6
falls and returns to its original state.

FIG. 3 shows another embodiment of the operating element circuit according to the present invention. In FIG. 3, the same reference numerals as in FIG. 1 indicate the same components.

The feature of this embodiment is that a voltage stabilization circuit 7 is provided in front of the analog time element circuit A and the digital time element circuit B for stabilizing the conditional input voltage, and that this voltage stabilization circuit 7 is free from circuit failures. The present invention is to include a circuit 8 that stops the time element output of the digital time element circuit B when an abnormality occurs.

When the voltage stabilizing circuit 7 as described above is provided, the DC voltage applied to the capacitor C4 of the time constant circuit constituting the analog time element circuit A is made constant, and the potential at point a, which is the charging voltage of the capacitor, is adjusted to the time element relay. Makima reaches the lifting voltage v1,
That is, the time element tdx of the analog time element circuit A can be made constant.

However, if a circuit failure occurs in the voltage stabilizing circuit 7, it will have a great effect on the analog time element circuit A and the time constant will go out of order. A circuit 8 is provided which stops the time element output of the digital time element circuit B when such occurrence occurs. Such a circuit can be easily realized using, for example, a comparator. In this embodiment, 1 derives a conditional input voltage from a position before the voltage stabilizing circuit 7 through a resistor R6, creates a reference power source from this conditional input voltage using a Zener diode D2, etc., and inputs this to the comparator 81. The output of the oscillation circuit 3 is input to the other input terminal of the comparator 81.

If an abnormality occurs in the voltage stabilization circuit 7, the voltage information at the two input terminals of the comparator 8 will be reversed from the normal state, so this can be used to stop the output of the comparator 8 and stabilize the voltage. To deal with abnormalities in the converter circuit 7. If the output of the comparator 81 stops, the operating time Td is extended infinitely, so it is fail-safe. In addition, in FIG. 3, 82 is an injector, D3 and D4 are diodes, and R7
~R1o is a resistor, and C5 is a capacitor.

Effects of the Invention As described above, the present invention provides an operation time element circuit in which an operation time element is determined with reference to the time when a condition is input, in which basic clock generation and counting operation are started by the condition input, and the count value is a digital time element circuit that outputs a time element determined by the time element, and an analog time element circuit that starts a time constant charging operation in response to the condition input and outputs a time element determined by the time constant; Since the operating time element is determined by the logical product of the outputs, it has a high fail-safe property and can determine the operating time element with high precision, and has a high degree of freedom in setting the operating time element, and its range is wide. It is possible to provide an element circuit with high reliability during operation.

[Brief explanation of the drawing]

Figure 1 is an electric circuit diagram of an operating element circuit related to unreleased 1!1,
Fig. 2 is a sequence diagram thereof, Fig. 3 is an electric circuit diagram in another embodiment, TtS4 is an electric circuit diagram of a conventional element circuit in digital operation, and Fig. 5 is an electric circuit diagram in analog operation in another conventional example. It is an electric circuit diagram of an elementary circuit. 2... Contact for condition input 3... Oscillation circuit 4... Counter 5... e-switch element 6... Time element relay Aφ... Analog time element circuit B... Digital time element circuit 1st Figure 2 Figure 3

Claims (4)

[Claims] (1) In an operating time element circuit in which an operating time element is determined based on the time when a condition is input, a digital time element circuit that starts generation of a basic clock and counting operation by the condition input and outputs a time element determined by the count value; , an analog time element circuit that starts a time constant charging operation in response to the condition input and outputs a time element determined by the time constant, and an operating time element is determined by the AND of the time element outputs of the two time element circuits. An operating elemental circuit characterized by: (2) The digital time element circuit starts operating in response to the condition input, and includes an oscillation circuit that generates a basic clock, and a time element circuit that counts the basic clock of this oscillation circuit and generates a time element when the counted value reaches a predetermined value. The analog time element circuit includes a time constant circuit constituted by a resistor connected in series with the condition input line and a capacitor charged through the resistor, and the analog time element circuit has a time constant circuit configured to output a counter. 2. The operating time element circuit according to claim 1, wherein the operating time element is determined by driving a time element relay by logical product of the output and the time constant time element output of the analog time element circuit. (3) The analog time element circuit applies the accumulated charge of the capacitor to one end of the time element relay, and the digital time element circuit applies the accumulated charge of the capacitor to one end of the time element relay, and the digital time element circuit applies the charge accumulated in the capacitor to the gate of a three-terminal switch element inserted and connected in series to the time element relay. The operating time element circuit according to claim 2, characterized in that it provides a time element output. (4) In an operating time element circuit in which an operating time element is determined based on the time when a condition is input, a digital time element circuit that starts generation of a basic clock and counting operation by the condition input and outputs a time element determined by the count value; , an analog time element circuit that starts a time constant charging operation in response to the condition input and outputs a time element determined by the time constant, and is provided in the preceding stage of the digital time element circuit and the analog time element circuit to stabilize the condition input voltage. An operating time element circuit comprising: a voltage stabilizing circuit for controlling the voltage stabilizing circuit; and a circuit for stopping the time element output of the digital time element circuit when an abnormality occurs in the voltage stabilizing circuit.