JPH02223341A - Switching circuit - Google Patents

Abstract

PURPOSE:To reduce material cost and to prevent miswiring by connecting all a plurality of switches to an AC power source and a load circuit in series. CONSTITUTION:By the operation of a load circuit 2 such as a lighting fitting 2e connected to an AC power source 1 through a contact 2A of a latching relay and built-in switches 3a, 3a' and 3b', switching circuits 3 and 3' that will be from a bidirectional conduction to only a single directional conduction are connected in series, which has a closed circuit where an end is connected to the AC power source 1 and the other end is connected to the other end of the AC power source 1 through a resistor 2d and a capacitor 2c and a series circuit composed of a bidirectional switching circuit 2b connected to both ends of the capacitor 2c and a coil 2a of a latching relay. In this way, all the switching circuits 3 and 3' are connected in series to the AC power source 1 and the load circuit 2. The material cost can thereby be reduced and miswiring can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an m-closed circuit, and more particularly to a switching circuit that is effective when turning on and off loads at a plurality of distant locations.

Conventional Technology The circuits shown in Figs. 4 and 5 are known as circuits using switching switches that can turn off loads such as lighting equipment at multiple distant locations. The circuit shown in the figure is one that can turn off neon lights, etc., at three separate locations. In the figure, 1 is an AC power supply, 2 is a load circuit for lighting fixtures, etc., and 3.3' and 3" are switching switches. It is a switch (switch circuit).

Problems that the invention aims to solve The connections of switches 3.3' and 3'' shown in Fig. 4 are °.

"off" state, and at this time, any switch 3.3
Even if you operate ', 3'', it will be in the "on" state.

- Once the switch is in the "on" state, either switch 3.
Even if you operate 3' and 3'', it will be in the "°°off" state. In this way, the circuit shown in Figure 4 applies loads at three separate locations.
It is widely used because it can be used both on and off.

FIG. 5 depicts the circuit of FIG. 4 as a more specific wiring diagram. As shown in Figure 5, each switch 3.3
', 3'' requires 3, 4, and 3 wires, respectively.
It is called the 4-way switch.

As the distance between each switch becomes longer, the material costs (wire cost, conduit cost, etc.) will be required because the distance between them will be connected using the above amount of wires.
The disadvantage was that it was expensive. Another drawback was that the connections were complicated and connections could easily be made incorrectly.

Further, although the circuits in FIGS. 4 and 5 have three locations, if the number of locations is increased to four or five, the cost of materials and the risk of connection wiring errors further increase.

The present invention has been made in view of the above-mentioned conventional situation,
SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a novel switching circuit which makes it possible to alleviate such drawbacks inherent in the prior art.

Differences between the invention and the prior art In contrast to the conventional switching circuit described above, the present invention can connect all the plurality of switches in series with the AC power supply, and the number of wires connected to each switch is only two. be. Compared to the conventional example of the three locations shown in FIG. 5, a total of four electric wires can be omitted, making wiring easier, reducing material costs, and preventing incorrect wiring.

Means for Solving the Problems In order to achieve the above object, the switching circuit according to the present invention has the following features:
An AC power source is created by connecting in series a load circuit such as a lighting device connected to an AC power source through the contacts of a latching relay, and a switch circuit that changes from bidirectional conduction to only one direction conduction by operating a built-in switch. a closed circuit in which one end is connected to the AC power supply and the other end is connected to the other end of the AC power supply via a resistor and a capacitor, and a series circuit of a bidirectional switch circuit and a latching relay coil connected to both ends of the capacitor. ing.

EXAMPLES Next, preferred embodiments of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a block diagram showing a basic embodiment of the present invention.

Referring to Figure 1, 1 is an AC power supply, 2 is a load circuit, and 3
．． 3' and 3'' indicate switch circuits, respectively. Wiring to each switch circuit 3.3' and 3'' is two electric wires each.
Load circuits can be turned on and off at any location.

FIG. 2 is a circuit configuration diagram showing a more specific first embodiment of the present invention. Although one switch circuit is omitted in the figure, the operation remains the same no matter how many switch circuits are used.

In Figure 2, 1 is an AC power supply and 2 is a load circuit.
2a is the coil of the latching relay, 2A is its contact, 2
b represents a bidirectional switch circuit, 2C represents a capacitor, 2d represents a resistor, and 2e represents a lighting device (for example, a fluorescent lamp) as a load. Further, 3 and 3' are switch circuits, 3a, 3a', 3b, and 3b' are switches, and 3c and 3c'
, 3d, 3d' are rectifier diodes, 3e, 3e',
3f.

3f' is a light emitting diode.

Next, to explain the operation of the circuit shown in Fig. 2,
The latching relay closes the contact 2A when a current flows through the coil 2a in the direction of the solid line and turns it off. When the current flows in the direction of the broken line, the latching relay opens the contact 2A and turns it off. Fig. 2 When each switch is not operated, a small current limited by the resistor 2d and capacitor 2C flows through the circuit, and an AC voltage is also applied across the capacitor 2C.At this time, the voltage is Since the switching voltage is set to be sufficiently lower than the switching voltage of the bidirectional switch circuit 2b, the bidirectional switch circuit 2b maintains an off state.

In the figure, when the switch 3a is operated, a current flows through the rectifier diode 3C and the light emitting diode 3e, the terminal of the capacitor 2c connected to the AC power source is positively charged, and its voltage increases. When the voltage reaches the switching voltage of the bidirectional switch circuit 2b, the capacitor 2C
The charged charge is discharged through the coil 2a of the latching relay in the direction shown by the solid line, and the contact 2A is closed to discharge the load 2e.
supply AC power to the

At this time, the light emitting diode 3e does not directly affect the operation, but if the load 2e is a device that operates with a slight delay, such as a fluorescent light, the switch section is there to indicate that it is operating. Good once used.

After the contact 2A is closed as described above, for example, the switch 3
When b' is operated, the capacitor 2C is charged through the rectifier diode 3d' and the light emitting diode 3f'' from the state where the AC voltage is applied, and the connection point side with the resistor 2d is positively charged. direction switch circuit 2b
When the switching voltage reaches , the charging charge discharges the coil 2a of the latching relay in the direction of the broken line, and the contact 2
Open A and turn it “off”.

At this time, the light emitting diode 3f' does not directly affect the operation, but it is better to use it once, such as when the lighting equipment of the load 2e is equipped with a cut-off timer or the like.

As explained above, a latching relay is operated by charging a positive or negative voltage to a capacitor by connecting a rectifier diode in series with a switch operated in a closed loop, and the number of switch circuits is limited in practical use. It is clear that there is no upper limit.

FIG. 3 is a circuit configuration diagram showing a second more specific embodiment of the present invention.

In FIG. 3, elements with the same reference numerals as in FIG. 2 are parts with the same function, and as is clear from FIG.

3c', 3d, and 3d' are connected in antiparallel, and by opening one of the circuits, the capacitor 2C is charged positively or negatively.

The light emitting diodes 3e and 3e' are lit when not in operation, and have the advantage of being able to display the position of the switch in darkness such as at night. In this second embodiment, rectifier diodes 3c, 3
Since a plurality of switch circuits such as c', etc. are connected in series, the upper limit of the number of switch circuits is determined by the voltage of the AC power supply 1 and the forward voltage of the rectifier diodes, etc., but this number does not pose any problem in practice.

In addition, the coil 2a of the latching relay in FIGS. 2 and 3
Although a one-turn type is shown, a two-turn type can also be operated in the same way by connecting rectifier diodes in series with each to set a current loop.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, all of the plurality of switch circuits can be connected in series with an AC source and a load, and a display function can be added if desired. In particular, it is highly effective in reducing material costs by omitting electric wires when there are a large number of switch circuits, in reducing costs by using existing wiring, and in preventing incorrect wiring.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a basic embodiment of the present invention;
FIGS. 2 and 3 show a more specific example of the present invention. FIG. 4 is a circuit configuration diagram showing a second embodiment. FIG. 5 is a circuit diagram showing an example of a conventional configuration. 1... AC power supply, 2... Load circuit such as lighting equipment,
3.3', 3''Mamma (switch DIR),
2a... Latching relay coil, 2A... Latching relay contact, 2b... Bidirectional switch circuit,
2c river capacitor, 2d...resistance, 2e...load (
lighting equipment), 3a. 3a', 3b, 3b' --- Switch, 3c, 3c',
3d, 3d'... Rectifier diode, 3F, 3F'.
・Light-emitting diode 1: Exchange J people, 1--Enter 2: P distance left Lt! Negative i of Bi each 3: t, 71 closed Z shi (switchro? each) Fig. 1 Fig. Fig.

Claims (1)

[Claims] A load circuit connected to both ends of an AC power source via the contacts of a latching relay, and a plurality of switch circuits that change from a bidirectional conduction state to a conduction state in only one direction by operating a switch are connected in series to the AC power supply. a closed circuit in which one end is connected and the other end is connected to the other end of the AC power source via a resistor and a capacitor, and a series circuit of a bidirectional switch circuit and a latching relay coil connected to both ends of the capacitor,
The capacitor terminal voltage when the switch of the switch circuit is not operated is set to be lower than the switching voltage of the bidirectional switch circuit, and the charging voltage of the capacitor when the switch is operated is set to be higher than the switching voltage of the bidirectional switch circuit. A switching circuit characterized in that a latching relay is driven by the discharge current of the capacitor.