JPH0354406B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a switch device that opens and closes an electric circuit.The present invention relates to a switch device that opens and closes an electric circuit.The present invention relates to a switch device that opens and closes an electric circuit. A central control device which connects in series the contacts of the operative electronic switch and another electromagnetically controlled auxiliary switch gear (switch) and which is further connected to the electronic switch before each change state of the switching state of the electromagnetically controlled switch gear mentioned above. The present invention relates to a switch device which subsequently reinterlocks this switch gear and closes the contacts of an auxiliary switch gear connected in series with the electronic switch.

Switching devices of this type are known and are disclosed, for example, in US Pat. No. 4,251,845. This known switching device is selected via a series of auxiliary relays, the switching order of which is predetermined by contacts inserted in the selection circuit. Here, this selection operation is affected by only the auxiliary contact of the electromagnetically controlled switch gear provided in the power supply circuit, separately from the switch on or switch off command, and this auxiliary contact allows both switch on and off. During this period, further progress in the switching order will be encouraged.

A disadvantage of this known switch device is that the switch-on time of the electronic switch must be relatively long. The reason for this is that there is a permissible value for the release time of the auxiliary relay. As a result, this electronic switch needs to absorb a corresponding amount of power loss and needs to be typed accordingly. Furthermore, in known circuits of this type, when the power supply circuit is opened, the switching order depends on the release delay time caused by the capacitor connected in parallel with the coil of the auxiliary relay. Therefore, during operation, changes in the capacitance of these capacitors can lead to failures in the switching operation, which in particular has the disadvantage of leading to destruction of the electronic circuit.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a switching device that can avoid erroneous selection operations of three switching elements.

This can be achieved according to the invention due to the following facts. That is, by providing a central control unit,
The unit is provided with independent selection circuits for each of the switching elements, and these selection circuits are provided with test loops connected to sensors, by means of which the switching states and/or selection operations of the switching elements are monitored. and these loops can be realized by linking each other according to instructions transmitted from a central control unit.

Therefore, as soon as a preceding switching command occurs, it is possible to proceed according to the next switching order. However, this makes it possible to proceed with safety intervals between the individual switching steps, as required in known cases. As a result, safety is increased and, furthermore, the switch-on time of the electronic switch can be reduced.

In addition, an auxiliary contact is provided to monitor the position of the contact of the electromagnetically controlled switch gear provided in the power circuit, so that the switching sequence continues only when the contact in the power circuit actually closes. It is characterized by what it did.

Further, according to the present invention, the switching state of the electronic switch is monitored by a sensor operating in response to its control current, and the selection of the electronic circuit is linked by the selection of an electromagnetically controlled auxiliary switch gear. , a signal is triggered when the selection of the electronic switch gear is completed, and this signal triggers a command to open the contact of the auxiliary switch gear via a delay element.

This allows the electronic switch to be isolated from the power supply circuit at the power supply, unlike the solutions previously known, for example from US Pat. No. 4,251,845. By this method, the electronic switch can be sufficiently protected against surges, short circuits, etc. on the load side. As a result, the contacts can be kept open. The reason for this is due to the magnitude of the current in the short-circuit region of the current path created by the contacts and, under certain circumstances, the generation of high induced voltages as well as extinguishing the formed arc. be.

The present invention will be described in detail below with reference to the drawings.

First, in FIG. 1, a magnetically, for example, electromagnetically controlled switch gear (switch) 1, 1' has a contact 4 provided in the power supply circuit, and by means of this contact, power supply terminals L1, L2, Controls the connection from L3 to load 5. In parallel with each of these contacts 4 and 4', a series connection contact 6,
6' are connected, and these contacts 6, 6' act as an isolator. These contacts 6, 6' belong to the auxiliary switch gears 2, 2', which are connected in series with the electronic switch 3.

According to FIGS. 2 and 3, auxiliary contacts 7, 7' and 8, 8' are provided to monitor the switching function of the switch gears 1, 1' or the auxiliary switch gears 2, 2', respectively.
1', the auxiliary switch gears 2, 2' and the electronic switch 3 as well as the contacts 7, 7', 8, 8' are connected to the central control unit 9.

This central control unit 9 is supplied with power from the power supply via the L1 phase and the neutral conductor, and is connected to conventional on/off buttons 10, 10' and 11, respectively. A fault warning device 12 is likewise connected to the central control device 9 .

According to the embodiment of FIG. 1, current transformers 13, 14 are provided by means of which the switching function of the switch gear 1 or the auxiliary switch gear 2 and the electronic switch 3 is monitored. Additionally, a current transformer can be provided for each phase for more precise monitoring.

In the switch arrangement of FIGS. 1 and 2, when the switch-on command is sent to the central control unit 9 by pressing the on-button 10, after the test loop has passed, the selection circuit for the auxiliary switch gear 2 is activated. operates, and its contacts close. The return signal is sent to contact 6 by auxiliary contact 8.
, the selection circuit of the electronic switch 3 is activated and this circuit is connected. This method allows the load 5 to be connected to the power supplies L1, L2, L3 via parallel current paths. After this, the electromagnetically controlled selection circuit of switch gear 1 is activated, so its contact 4
will close.

After the return signal arrives via the closed circuit of the contact 4 of the switch gear 1 by means of the auxiliary contact 7 or the current transformer 13, the electronic switch 3 is blocked, after which the selection circuit of the auxiliary switch gear 2 is reset again and the auxiliary Contact 6 of switch gear 2 is opened again. Of course, instead of monitoring only one phase, all three phases can be monitored by transformer 14.

Off button 1 connected before on button 10
When 1 is pressed, the selection circuit of the auxiliary switch gear 2 is activated and the contact 6 is closed, since the switching-off command triggered by pressing the off button has priority over the switching-on command. .

After the return signal has been transmitted via the closed circuit of the contact 6, but at the latest after a certain period of time, the selection circuit of the electronic switch 3 is activated, so that this switch 3 becomes conductive.

As soon as the return signal corresponding to the built-through connection of the electronic switch 3 arrives, but at the latest after a certain time has elapsed, the selection circuit of the switch gear 1 is reset and the contact 4 is opened. When this happens, the selection circuit of the electronic switch 3 is reset, the electronic switch 3 goes into a blocked state, and the selection circuit of the electronic switch 3 is reset at the latest after a certain period of time has elapsed.

After the selection circuit of the electronic switch 3 is reset, the selection circuit of the auxiliary switch gear 2 is reset, so that its contacts 6 are opened and the switching-off cycle is completed.

In the embodiment shown in FIG. 3, switching-on and switching-off cycles are performed in the same manner. Now, depending on whether the on button 10 or 10' is pressed, the auxiliary switch gear 2
or 2' is selected as the next order of switch gear 1 or 1' by closing contacts 6 or 6' and 4 or 4'.

However, before the appropriate selection of auxiliary switch gear 2 or 2', a test is carried out in a test circuit whereby none of the coils of switch gear 1, 1' and auxiliary switch gear 2, 2' are energized and It is tested whether any of the contacts 4, 4' and 6, 6' are closed. Furthermore, the selection circuits of the auxiliary switch gears 2, 2' and the switch gears 1, 1' are mutually locked, so that when a switch-on signal arrives, for example, at the selection circuit of the auxiliary switch gear 2, a blocking signal is transferred to the auxiliary switch gear. 2' and the selection circuit of switch gear 1'. These switch gears can therefore be activated after a switch-off command and a subsequent switch-on command triggered by pressing the on button 10.

By connecting the electronic switch 3 in parallel to the load side of the auxiliary switch gears 2, 2', a single electronic switch 3 can connect the contacts 4, 4 of the switch gears 1, 1'
It can operate in both circuits in parallel with 4'.

A block diagram of a central control unit 9 for a switch arrangement according to FIG. 1 or 2 is shown in FIG. 4, with the voltage supply omitted.

On and off button 1 during central control unit
The instructions introduced via 0 and 11 are stored in memory 15. The output terminal of this memory 15 is connected to each of selection circuits 16, 17, and 18, and each of these selection circuits is assigned to one of the switching elements of the switch gear. In particular, it is assigned to auxiliary switch gear 2, electronic switch 3, and switch gear 1. Furthermore, the output terminal of the memory 15 is also connected to the test circuit 19.

This test circuit 19 is connected to a sensor 20 which is responsive to the current flowing through the coil of the electromagnetically controlled switch gear 1. Also, the position of the contact 4 of the switch gear 1 is monitored by this sensor 20, and the switch state of the electronic switch 3 is monitored by the sensors 7, 13 and the sensor 21 connected to the auxiliary contact 7 or the current transformer 13, for example. , for example in response to the voltage supply to the ignition electrode of the electronic switch 3 and/or to the current flowing through the parallel circuit. This test circuit 19 also receives signals from a sensor 22 depending on the current passing through the coil of the auxiliary switch gear 2 and from a sensor 23 monitoring the switch state of the contacts 6.

When a switch-on command arrives at the test circuit 19, this circuit 19 sends the switch command to the selection circuit 16 of the auxiliary switch gear 2. If the current flowing through the coil of the switch gear 1 or the auxiliary switch gear 2 is zero, these contacts 4 or 6 are in the open position and the electronic switch 3 is also in the blocked state.

When not in this state, the switch-on command to the selection circuit 16 of the auxiliary switch gear 2 is interrupted, and a signal for the failure warning circuit 24 is transmitted.

This switch-on command to the selection circuit 16 is simultaneously sent to a resettable timing element 25, which is connected to the reset input of the selection circuit 16, so that after the end of the operating time, A signal is sent to the reset input terminal of the selection circuit 16, causing it to reset again. At the same time, this signal also activates a fault warning circuit 24, by means of which the lamp 12, for example, is controlled.

However, the timing element 2 is connected to a sensor 23 that monitors the contacts 6 of the auxiliary switch gear 2.
The operation in step 5 is interrupted in the following cases. That is, this is a case where the closing of the contact 6 is announced during the operation time of the timing element 25.

The closing of contact 6 of auxiliary switch gear 2 is sensor 2
As soon as the selection circuit 16 connected to the electronic switch 3 is notified, this selection circuit sends a switch-on command to the selection circuit 17 which controls the electronic switch 3. This switch-on command is transmitted to the timing element 26.
can be delayed to prevent through-connection of the electronic switch 3 during burnout of the contacts 6.

When a switch-on command arrives from the selection circuit 16 to the selection circuit 17 connected to the sensors 7, 13, 21 and 23, it tests whether the contact 4 is still open, but whether the contact 6 is closed. . In such a case, the control electrode of the electronic switch 3 receives a firing pulse or continuous signal and thus maintains the through-connection condition. If the above conditions are not met,
The control electrode of the electronic switch 3 no longer receives anything, and the failure warning circuit 24 becomes activated. At the same time, a command to open the contact 6 is given to the selection circuit 16 of the auxiliary switch gear 2.

If a signal does not arrive at the control electrode of the electronic switch 3 within a certain time after the switch-on signal arrives in the selection circuit 17, or if no current flows in the parallel circuit, the failure warning circuit 24 is activated. A command for activating and opening the contacts 6 is transmitted to the selection circuit 16, and this state is monitored by a sensor 21 connected to the selection circuit 17.
In this case, the selection circuit 17 is reset.

On the other hand, when a signal corresponding to a suitable through connection of the electronic switch 3 arrives from the sensor 21, a switching signal is sent from the selection circuit 17 to the selection circuit 18, and this circuit 18 is assigned to switch gear 1. acts to urge the contact 4 to close as a result of the switch-on signal from the memory 15. At the same time, this signal arrives at a resettable timing element 27, the output of which is connected to the reset input of the selection circuit 18 and also to the fault warning circuit 24.

If a signal corresponding to the closed contact 4 of the switch gear 1 arrives at the timing element 27 during its operating time, this element 27 is reset and the transmission of the reset signal to the selection circuit 18 is no longer carried out, as well as a failure. The sending of the signal that activates the warning circuit 24 is also stopped.

In the opposite case, the reset of the selection circuit 18 and the activation of the fault warning circuit 24 take place, and the timing element connected to the output terminal of the timing element 27 and also connected to the reset input terminal of the selection circuit 17 is activated. Through 28, the selection circuit 1
As a result, the electronic switch 3 becomes blocked.

However, if the signal corresponding to the closed contact 4 arrives at the timing element 27 and the selection circuit 18 within the set time, the selection circuit 18 sends the selection circuit 17 a signal to block the electronic circuit 3. Instructions are sent.

As soon as the return signal from the sensor 21 reaches the control circuit 17 via the electronic switch blocking state, from this circuit 17 to the selection circuit 16 the timing element 2
6, a signal for opening the contact 6 of the auxiliary switch gear 2 is sent. If a return signal of this type arrives within a certain time, the fault warning circuit 24 is activated and a signal is sent to the selection circuit 16 to open the contact 6.

This selection circuit 16 supplies a command to open the contact 6 to the auxiliary switch gear 2, and checks whether a signal corresponding to the opened contact 6 has arrived from the sensor 23 within a specific time. If this does not occur, the selection circuit 16 sends a signal which activates the fault warning circuit 24, but retains the command to open the contact 6 and does not reset it.

When a switch-off command arrives at the central control unit by pressing the on button 11, this command is stored in the memory 15, by means of which the test circuit 19 and the selection circuit 16, 17 are transmitted from its output terminals. and sends the signal arriving again at 18.

This test circuit 19 checks whether the contacts 4 of the switch gear 1 are closed and whether the electronic switch 3 is blocked. If such a condition does not occur within a specified time, the fault warning circuit 24 becomes activated. However, in both cases,
The command to close the contacts 6 of the auxiliary switch gear 2 is transmitted to the selection circuit 16 and the reset input connected to the timing element 25 is deactivated by means of the switch-off signal coming from the memory 15. Furthermore, if a switch-off signal from memory 15 is present, the transmission of a switch-on command to selection circuit 17 is started after a certain time. This starting operation takes place irrespective of whether the sensor 23 supplies or does not supply a signal corresponding to the closed contact 6 within a predetermined time. However, if this type of signal does not pass, the fault warning circuit 24 will be activated after the timing element is activated.

The switch-off signal coming from memory 15 ensures that: That is, even if the signal corresponding to the closed contact 6 does not exist when the switch-on command arrives from the selection circuit 16, the selection circuit 17 causes the electronic switch 3 to enter the through-connection state, and at the same time outputs the switching signal. It is reserved to feed the selection circuit 18. This circuit 18 controls the switch gear 1 so that the contacts 4 open as a result of a switch-off signal coming from the memory.

When a signal corresponding to the open contact 4 is supplied from the sensors 7 and 13, the selection circuit 18 sends this switch 3 to the selection circuit 17 of the electronic switch 3.
sends a signal to block the However, if this signal does not appear, the timing element 27 is activated, the fault warning circuit is activated, and a signal arrives at the selection circuit 17 for blocking after the activation time of the timing element 28.

As a result, the electronic switch 3 is blocked, and
After a signal corresponding to a suitable blocking state of the electronic switch 3 arrives from the sensor 21 or after a predetermined time has elapsed, the contact 6 of the auxiliary switch gear 2 is activated.
The selection circuit 17 selects the signal to release the signal from the selection circuit 16.
In this latter case, the failure warning circuit 24
will start working.

This selection circuit 16 controls the auxiliary switch gear 2 for opening the contact 6, and also checks whether a signal corresponding to the opening of the contact 6 has arrived from the sensor 23 within a specific time. . If this is not the case, for example
The failure warning circuit 24, which can be configured with an OR gate, is activated, but the auxiliary switch gear 2 for opening the contact 6
maintain control of

This ensures that the switch-off command is executed in all cases, even if a fault occurs during a switching operation.

In the block diagram of FIG. 5, a memory 15 with two input terminals is provided, which is interlocked in connection with the switch-on command and is assigned to each of the two on-buttons 10, 10'. However, these switches are designed to be in the same switch state when a switch-off command arrives. Therefore, only one of the two output terminals of the memory 15 can transmit a switch-on signal, and this signal can be transmitted to one or both of the on-buttons 10,1.
Off button 1 regardless of whether 0' is pressed or not
Hold until you press 1.

This test circuit 19 is connected not only to sensors 20, 7, 22 and 23 that monitor switch gear 1 and auxiliary switch gear 2 or their contacts 4 and 6, but also to sensors 20' and 7 that monitor switch gear 1' and auxiliary switch gear 2'. ', 22' and 23' furthermore a sensor 2 which monitors the electronic switch 3.
Also connect to 1. Furthermore, this test circuit
Two output terminals of the memory 15 are also connected via the OR gate 30. Switch-on instruction is OR gate 3
0 to the test circuit 19, this circuit confirms that no current is flowing in any coil of the switch gears 1 and 1' and the auxiliary switch gears 2 and 2', and that no current is flowing in any of the contacts 4 or 4' and 6 or 6. ' is not closed and whether electronic switch 3 is also in the locked state. If these conditions are met,
This test circuit 19 transmits a switching command, and this command is sent to two selection circuits 16, 16'.
via one of the two AND gates forming a link with one of the two output terminals of the memory 15, and these circuits 16, 16' are assigned to the auxiliary switch gears 2 and 2', respectively. do. At the same time, the two selection circuits are interlocked. The reason for this is that the output terminals of the AND gates 31 and 32 are connected to the set input terminal of one of the selection circuits 16 and 16', and the reset input of the other selection circuit 16 and 16' is connected via the OR gates 33 and 34. This is because it is also connected to the terminal. The two input terminals are connected to the timing element 25.
A sensor 7 is connected to the output terminal of the auxiliary switch gear 2, 2' to monitor the position of the contacts 6, 6' of the auxiliary switch gears 2, 2'.
and 7', which can be reset during operation by a signal from one of the two sensors. This signal corresponds to the closed position of these contacts.

According to the embodiment of FIG. 5, the switch-on and switch-off operations are basically identical to those of FIG. 4, and the fault warning circuit 24 also operates under the same conditions.

Similar to the test circuit 19, the selection circuit 17 of the electronic switch 3 is connected to the two output terminals of the memory 15 via an OR gate 30. Furthermore, the selection circuit 17 is connected to the sensors 7 and 7' which monitor the positions of the contacts 4, 4' and also to the sensors 23 and 23' which monitor the contacts 6, 6'. When the switch-on command arrives from the selection circuit 16, 16' via the timing element 26, the selection circuit 17 determines whether the contacts 4, 4' are still open.
and checks whether the contacts 6 or 6' (but not both contact groups 6 and 6') are closed, and then selects only the control electrode of the electronic switch 23, so that the electronic switch becomes a through connection.

A signal representing this state of the electronic switch is sent to sensor 2.
1 to the selection circuit 17, this circuit 17
A switching signal is sent by the switch, which signal is sent to one of the two selection circuits 18, 18' via one of the AND gates 35, 36, which have a second input terminal connected to the output terminal of the memory 15. supply.
These circuits are distributed to switch gears 1 and 1', respectively. At the same time, a timing element 27 is started which can be reset by a signal corresponding to closed contact 4 or 4'.

The output terminals of the AND gates 35 and 36 are connected not only to the set input terminals of the selection circuits 18 and 18', but also to the set input terminals of the selection circuits 18 and 18'.
It is also connected to OR gates 38 and 37. These OR
The output terminals of the gates 38 and 37 are selected by the circuits 18 and 1.
8', and its second input terminal is connected to the output terminal of timing element 27.

As a result, the interlock of the selection circuits 18, 18' is executed again.

As soon as the signals corresponding to the closed contacts 4 and 4' reach the respective selection circuits 18 and 18' from the corresponding sensors 7 and 7', a command is issued from these circuits to the selection circuit 17 to block the electronic switch 3. Given.

A signal is applied to both selection circuits 16, 16' which causes contacts 6 and 6' to open, but a further course of the switch-on cycle takes place as in the embodiment of FIG.

When the same signal is supplied from the two output terminals of the memory 15, which means a switch-off signal, the test circuit 19 determines whether the contacts 4 or 4' of the switch gear are closed and the electronic switch is blocked. Check if it is. In either case, the switching instruction is sent from the test circuit 19 to the two AND gates 39, 40.
, and its input terminal is connected to the output terminal of the OR gate 30, so that this terminal is only connected in case of a switching-off command. Since the third input terminal of these gates 39, 40 is connected to sensors 7 and 7', it is not possible to connect only the above-mentioned input terminals of these gates, which are connected to sensor 7 or 7' and thereby closed. A signal corresponding to contact 4 or 4' is supplied.

Up to the transmission of the switching signal from the selection circuit 17 to one of the selection circuits 18, 18', the next course of the switching-off cycle is equivalent to the cycle described in FIG. 4.

When the switching off command appears on the two output terminals of the memory 15, the switching signal is
It is fed via an AND gate 41 whose inverting input terminal is connected to the output terminal of the OR gate 30 and can therefore only be connected in the case of a switching-off command. The output terminal of this AND gate 41 is connected to the set input terminal of the selection circuit via anti-coupling elements 42, 43 such as diodes, so that the combined switch gears 1, 1 are connected to the set input terminal of the selection circuit for opening the contacts 4, 4'. ' is controlled by the result of the switching-off command present.

These further steps in the switching-off cycle are the same as described in connection with FIG.

[Brief explanation of drawings]

1 and 2 are block diagrams showing an embodiment of the switch device of the present invention, FIG. 3 is a block diagram of the same switch device when it is connected to/disconnected from a load, and FIG. 4 is a block diagram similar to the one shown in FIG. Alternatively, FIG. 2 is a block diagram of the central control unit, and FIG. 5 is a block diagram of the central control unit of FIG. 1, 1'...electromagnetic control type switch gear, 2,
2'...Auxiliary switch gear, 3...Electronic switch,
4, 4', 6, 6'...Contact, 5...Load, 9...
Central control unit, 10, 11...on, off button, 12...failure warning circuit, 15...memory,
16-18...Selection circuit, 25-27...Timing element, 20-23...Sensor.

Claims (1)

[Claims] 1. An electronic switch and a second magnetically controlled auxiliary switch gear, which act as an isolator and are connected in series, are connected in parallel to each contact point of the first magnetically controlled switch gear, which is provided in the power supply circuit to be switched. , the first switch gear provided in the power supply circuit is connected to the power supply circuit via the electronic switch before the switching state changes, and is connected again after the switching state of the first switch gear changes. In the switching device, the switching element 1 is provided with a control unit that opens and closes an electric circuit by closing the contact of the auxiliary switch gear connected in series with the electronic switch.
A central control unit is provided with a separate selection circuit 16, 16', 17, 18, 18' for each of said switching elements 1, 1', 2. .