JPS5951697B2 - Auxiliary relay circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an auxiliary relay circuit for increasing contact width, and particularly to a circuit technique for effectively monitoring the response state of an auxiliary relay.

Conventionally, when using an auxiliary relay to increase the open/close state of a switch or contact, a keep relay (also referred to as a stop relay) that mechanically or magnetically maintains the operating state has been used.

In this case, it is necessary to monitor whether the kit relay is responding correctly to the state of the Kawahara contact point.

FIG. 1 is a diagram showing one embodiment of a conventional system.

In the figure, la and lb are original contacts, which have opposite opening and closing states to drive the kit relay.

In this figure, K is a kit relay, which has an operating coil KO, a return coil KR, and opening/closing contacts Ka and Kb.

This relay is set to the Ka side by KO excitation, and set to the Kb side by KR excitation.

KA and KB are contacts that open and close together with the kit relay; KA is closed and KB is opened by Ko excitation, and reversed by KR excitation.

Reference numeral 2 denotes an auxiliary relay, which has a contact 2b that opens when operating and closes when returning.

3 is a time-limited relay for abnormality detection.

Note that P and N are power supplies. In this circuit, 1a open,
When 1b is closed, as shown in the figure, the kit relay is on the Kb side, KA is open, and KB is closed.

2b is opened due to the operation of relay 2.

Now, when the state of the original contact becomes 1b open circuit and 1a closed circuit, the operation is as follows.

By opening 1b, the excitation of relay 2, which has been in an operating state in the circuit P-1b-KB-2-N, is released.

Next, due to the cycle of 1a, p-1a -Ko-Kb-N(
7) In the circuit, the stop relay K operates, opening Kb and closing KA.

Due to the operation of the operating coil Ko, KA is closed and K8 is opened, so that the relay 2 is activated again in the circuit of P-1a-KA-2-N.

During this switching, relay 2 temporarily becomes inactive and closes contact 2b, but when switching is performed correctly, 2b opens immediately, so time-limited operation relay 3 for abnormality detection operates. There isn't.

On the other hand, if the kit relay is unresponsive (la is quiet, Ko is not working), Ka and KA remain open, and relay 2 continues to be in a non-energized state, so 2b is closed. , P-2b-3-N circuit, the relay 3 detects an abnormal response of the kit relay.

On the other hand, FIG. 2 shows a conventional example in which the same monitoring as in FIG. 1 is performed using an indicator light RG.

In this circuit, when 1a is open and 1b is closed, the kit relay is on the Kb side, KA is open, and KB is closed, as shown.

As a result, the indicator lamp G is lit and the indicator lamp R is turned off.

Now, when the state of the original contact becomes 1b open circuit and 1a closed circuit, the operation is as follows.

Due to the 1b opening, the indicator light G, which has been lit in the P-1b-KB-G-N circuit, is turned off.

Next, due to the closing of 1a, the kit relay K is operated in the circuit P-1a-KO-Kb-N, and Kb is opened and KA is closed.

Further, due to the operation of the operating coil Ko, KA is closed and KB is opened, so the indicator light R is turned on in the P-1a-KA-R-Ncy'>circuit.

Therefore, when the kit relay K is responding correctly, except for the moment when the original contacts 1a and lb are switched, the indicator lights R and G
One of the two is always lit.

On the other hand, if the power relay K is unresponsive (Ko does not work even though it is quiet), Ka and K remain open, and therefore the indicator light R is not lit.

At this time, the indicator light G is also not lit due to the opening of the contact 1b.

As a result, the two indicator lights R,
This is confirmed by the fact that neither G is lit.

As described above, the conventional monitoring method shown in FIGS. 1 and 2 is effective, but when the original contacts 1a and lb are switched, the contact Ka
, If Kb does not work, the following problems may occur.

In other words, state 1b in Figure 1, Kb, KB closed, 1a
, Ka, KA open) to 1b closed. Suppose that KA is closed and KB is opened, but Kb is not switched to Ka.

At this time, the operation of relay 2 continues, and a failure in the relay cannot be detected.

In the example shown in FIG. 2, the display only changes from G to R, and no abnormality can be displayed.

At this time, not only is it not possible to display an error, but the power supply
, N will be connected continuously for a short period of time, and there is a possibility that twisting loss will occur.

Generally, in order to ensure reliable relay operation, a kit relay uses coil opening/closing contacts Ka and K rather than wide contacts KA and KB.
In order to delay the response timing of b, Ka, K
The problem of only b not working cannot be ignored.

In view of the above, it is an object of the present invention to provide an auxiliary relay circuit that can reliably detect a phenomenon in which only Ka and Kb are inoperative.

An embodiment of the present invention is shown in FIGS. 3 to 6.

First, Fig. 3 shows an example of the conventional circuit system shown in Fig. 1, in which 4 is a voltage relay whose coil resistance is larger than that of KO and KR.
The movement is equivalent to the voltage relay 2 in FIG.

REC1 and RFC2 are backflow blocking elements (e.g. diodes), and KA and KB are state contacts that are amplified from the original contacts 1a and lb, which open and close depending on the operation and return state of the kit relay. It is equivalent to KB.

As shown in the figure, backflow blocking elements in opposite directions are connected in series to these contacts to form a parallel connection, which is then connected in series with the voltage relay 4.

Now, when the states of original contacts 1a and lb are 1b closed and 1a open, P-1b-KR-4-KB-REC2
In the -Kb-N circuit, relay 4 operates, but most of the voltage applied to the KR coil is the operating voltage between P and N because the coil resistance of relay 4 is sufficiently large compared to that of KR. Since it is applied to relay 4, it becomes a sufficiently small value, so KR does not move for the time being.

Next, when the original contact 1b is open and 1a is closed, P-1a
A voltage between P and N is applied to the operating coil Ko of the relay in the -KO-Kb-N circuit, and the relay is switched to the operating state.

When relay K is activated, Kb and KB are open, and Ka is open.
, KA is closed, so p-1a -Ko-REC1
-KA-4-Ka-N circuit is formed.

At this time, the relay has a transient state of operation (Kb, KB to Ka
, at the time of switching to KA), relay 4 had returned to its original state, but it becomes operational again.

That is, like the relay shown in FIG. 1, the relay 4 returns only while the original contact is being switched while the relay K is switching the original contact, but as long as the relay K is normal, the time during the return is as follows. This is a very short time, about the same as the response time for a relay.

In short, as long as the auxiliary relay circuit is normal, relay 4
is constantly energized and continues to operate.

In addition, when the circuit of P-1a-KO-RECl-KA-4-Ka-N is formed, KO does not operate.
The same is true for R.

Here, if relay 4 is in the state of 1b closed, P-1b-
In the KR-4-KB-REC2-Kb-N circuit, 1
If a is closed, p-1a -K.

-RECl--KA-4-Ka-N circuit will be excited, and this is the state when the circuit is healthy.

Therefore, if at least one of KB and Kb is open when 1b is closed, or at least one of KA and Ka is open when 1a is closed, relay 4 becomes non-energized, 4b returns, and relay 3 detects an abnormality.

Therefore, even when the opening/closing contacts Ka and Kb are not operating in the conventional system, this can be detected.

FIG. 5 shows another embodiment of the present invention, in which REC,
The circuit consisting of KA, KB, and 4 is relay Ko.

The difference from FIG. 3 is that the opposite contacts 1a and 1b of KR are provided on the lb side.

But in any case, lb. 4. KB, Kb or 1 a, KA, 4. Since the relay 4 is excited by connecting Ka in series, it is clear that the same effect as in the case of FIG. 3 is obtained.

The fourth example shows an embodiment applied to the display circuit shown in FIG. 2, and the example shown in FIG. a is different in that indicator lights R and G are used in place of the relay 4 shown in FIG.

If this circuit is healthy, when 1b is closed, P-1b-
By the circuit of KR-G-KB-REC2-Kb-N, 1a closed throat P-1a -Ko-REC1-KA-R
-Ka-N circuit turns on one of indicator lights R and G.

In this kit relay, when the series circuit is not formed, the indicator lamp goes out to indicate an abnormality.

In this circuit, indicator lights R and G are relay KO like voltage relay 4.

It is assumed that the resistance value is sufficiently large compared to KR.

The figure shows an example in which light emitting diodes LED are used in place of indicator lights R and G, and the resistance R is sufficiently large compared to KO and KR.

Figure 6 is a modification of Figure 4, with anti-contact points 1a of KO and KR,
This is an example provided on the lb side.

The operation of this circuit is similar to the fourth circuit.

The figure shows an example using LEDs.

According to the circuit of the present invention described in detail above, since the monitoring targets include the coil opening/closing contacts Ka and Kb of the kit relay and the expanded representative contacts KA and KB,
It is possible to reliably detect an abnormality in a case where the expanded contacts KA and KB respond and the coil opening/closing contacts Ka and Kb do not respond (and vice versa).

In addition, in the embodiments shown in FIGS. 3 and 4, it is possible to constantly monitor the previously operated relay coil (coil KR in the state after switching to lb closed) among KO and KR, and the implementation shown in FIGS. In the example, the relay coil to be operated next (coil KO in the state after switching to lb closed) can be constantly monitored.

[Brief explanation of the drawing]

1 and 2 are conventional circuit diagrams, and FIGS. 3 to 6 are circuit diagrams showing one embodiment of the present invention. K...Kitsupurirei, KO, KR...
Operating coil and foot coil, Ka, Kb...
・A contact, B contact, 2. 3. 4... Relay for abnormality detection.

Claims (1)

[Claims] 1 A first series circuit connected between the power supply bus bars and consisting of a first contact, a first relay coil, and a switching contact, and a first series circuit connected between the power supply bus bar and comprising a second contact, a second relay coil, and the switching contact. and a second series circuit consisting of contacts, the first contact and the second contact are interlocked reverse contacts, and the switching contact is switched to the second series circuit side by the operation of the first relay coil. In the auxiliary relay circuit configured to be switched to the first series circuit side by the operation of the second relay coil, the first and second contact sides of the first relay coil and the second relay coil, or Between these relay coils on the switching contact side, a first relay coil including at least a contact that closes when the first relay coil is energized and a first diode.
a second abnormality detection series circuit including at least a contact that closes when the second relay coil is excited, and a second diode whose direction is opposite to that of the first diode. An auxiliary relay circuit characterized by: