WO2008062283A2

WO2008062283A2 - Electric socket with external power-on switch

Info

Publication number: WO2008062283A2
Application number: PCT/IB2007/003570
Authority: WO
Inventors: Giovanni Pirondini; Eugenio Caratti
Original assignee: Pircar S.R.L.
Priority date: 2006-11-20
Filing date: 2007-11-20
Publication date: 2008-05-29
Also published as: WO2008062283A3; ITSO20060001U1

Abstract

An electric socket comprises: a casing (4); an input line (5), which can be connected to a network terminal (2) of an electric power main (3); at least one output connector (7); and a selective coupling stage (8), for selectively coupling and decoupling the output connector (7) and the input line (5). The electric socket also comprises a power supply source (13) and a switch (10) for selectively connecting the power supply source (13) to a control terminal (16a) of the selective coupling stage (8), wherein the switch (10) is arranged outside the casing (4).

Description

ELECTRIC SOCKET WITH EXTERNAL POWER-ON SWITCH

TECHNICAL FIELD

The present invention relates to an electric socket with external power-on switch. BACKGROUND ART

As is known, currently marketed multiple sockets for connecting household and office appliances to the electric power main incorporate a power-on and power-off switch mounted on the multiple socket. In particular, the switch is arranged on the casing of the socket and is connected along a line that supplies power to the connected appliances .

This type of socket is increasingly used because it allows the appliances to be disconnected from the electric power main during periods of time in which they are not used. This reduces the risk of faults caused by current overloads and results in a notable saving of energy, especially in case of appliances with a standby function. Such appliances often stay in standby mode for many hours every day. Although power consumption in standby mode is very low, it is not nil, and, in time, is certainly not negligible. Sockets with a switch are a practical means for enabling the user to completely eliminate power consumption by all the connected appliances . As the switch is mounted on the socket, the socket must be installed in an exposed and accessible position so that it is possible to operate the switch.

Furthermore, the manoeuvres required to switch the socket on and off inevitably involve coming into contact with parts that are adjacent to or directly powered at the line voltage (normally 110 V or 220 V, depending on the country) . It is clear that this exposes the operator to the risk of electrocution, especially when the socket is located in a position that is not easily accessible and not visible, as is not infrequently the case. In such cases, the user must try to locate the switch on the socket by feel. Moreover, operating the switch is difficult and the user is often tempted to leave the socket in the "on" position (switch closed) . The advantages are thus rendered ineffective.

DISCLOSURE OF INVENTION

The purpose of the present invention is to provide an electric socket that overcomes the drawbacks described above.

According to the present invention, an electric socket is provided as claimed in claim 1. BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the present invention, some non-limiting embodiments thereof will now be described by way of example with reference to the accompanying drawings, in which:

- figure 1 shows a simplified block diagram of an electric socket according to a first embodiment of the present invention; - figure 2 shows a more detailed block diagram of the electric socket in figure 1;

- figure 3 shows a simplified block diagram of an electric socket according to a second embodiment of the present invention; - figure 4 shows a more detailed block diagram of the electric socket in figure 3; and

- figure 5 shows a block diagram of an electric socket according to a third embodiment of the present invention; and - figure 6 shows a block diagram of an electric socket according to a fourth embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Basically, the device according to the invention allows sockets and multiple sockets for connecting household and office appliances to the electric power main to be controlled, by a system comprising a button arranged outside the socket and a selective coupling stage powered by a battery or by a mini power supply unit.

According to one embodiment, a multiple socket comprises at least a casing, an input line, connectable to the terminal of an electric power main.

In the examples illustrated in the accompanying drawings, the device comprises a multiple socket, in which there is housed a device for controlling connection to and disconnection from the power main

(selective coupling stage) , and a button arranged externally and connected to said multiple socket by means of a bipolar cable with a termination jack. According to some embodiments, the device for controlling connection to and disconnection from the power main (selective coupling stage) arranged inside the multiple socket comprises an impulse relay, a triac, a galvanic decoupling device and a battery or mini power supply unit.

The version with mini power supply unit is provided with a button that is back-lit by one or more LEDs to indicate the position of the button in a dark environment . With reference to figures 1 and 2, reference number 1 indicates a multiple safety socket for simultaneously connecting a plurality of electric appliances to a terminal 2 of an electric power main 3. For example, the power main 3 supplies a line voltage V_N of 220 V. The multiple socket 1 comprises a casing, 4, an input line 5, which can be connected to the terminal 2 of the power main 3 by means of a plug 6, a plurality of output connectors 7, incorporated in the casing 4, and a selective coupling stage 8, housed inside the casing 4 and connected between the input line 5 and the output connectors 7. The selective coupling stage 8 is controlled by a switch button 10, outside the casing 4 and removably connected by a cable 11 and a connector 12. In particular, the length of the cable 11 is such that the switch 10 may be arranged at a distance from the casing 4 (for example, between 0.5 m and 3 m) . The switch 10 is of the normally open type and returns to the home position after it has been pressed. The power required to operate the selective coupling stage 8 is supplied by a battery 13, which is also housed inside the casing 4. The battery supplies a safety voltage V₃ preferably of less than 24 V. In the embodiment described here, the safety voltage V_s is equal to 12 V.

As illustrated in figure 2, the selective coupling stage 8 comprises a relay 15, a triac 16 and a galvanic decoupling device, for example a photo-coupling device 17. The relay 15 is of the impulse type, i.e. it switches alternately between a conducting state and a cut-off state each time its control coil 15a receives a pulse. The relay 15 has first conduction terminals 15b connected to the input line 5 and second conduction terminals 15c, connected to the output connectors 7, which are arranged in parallel . The coil 15a is of the high control voltage type, that is it requires a voltage substantially equal to the line voltage in order to be operated. Control terminals 15d of the coil 15a are connected to the input line 5. More specifically, one of the control terminals 15d is directly connected to a first conductor of the input line 5, while the other control terminal 15d is connected to a second conductor of the input line 5 via the triac 16 (in particular, via the conduction terminals of the latter) .

Control terminals 16a of the triac 16 are connected to the battery 13 via the photo-coupling device 17 and, selectively when closed, via the switch 10. More specifically, the switch 10 has a first terminal connected to the battery 13 and a second terminal connected to the photo-coupling device 17, which is in turn connected to the control terminals 16a of the triac 16. When the switch button 10 is operated the battery 13 powers the galvanic decoupling device, which triggers the triac 16 which in turn energizes the coil 15a of the impulse relay 15, connecting and disconnecting the multiple socket 1 to and from the electric power main 3. As mentioned previously, the relay 15 is of the impulse type and switches alternately between the conducting state and the cut-off state each time the coil 15a receives a pulse on the control terminals 15d. Pulses are supplied when the switch button 10 is pressed, so that it temporarily connects the triac 16 to the battery 13 via the photo-coupling device 17. The triac 16 conducts and couples the control terminals 15d of the coil 15a to the input line 5. The coil 15a receives the line voltage and the relay 15 thus switches . In this way, the multiple socket 1 may be activated and deactivated easily so that power is supplied selectively to the equipment connected thereto . When the multiple socket 1 is deactivated, the equipment is disconnected from the power main 3 and consumption is nil. The switch 10 is only connected to a low voltage source, namely the battery 13, and can thus be operated by the user in complete safety. Furthermore, in the embodiment herein described, the use of the photo- coupling device 17 means that the low voltage part of the multiple socket 1 can be kept separate from the high voltage part and the power main 3.

In the embodiment described in figures 3 and 4, in which parts that are the same as those described previously are indicated by the same reference numbers, a multiple socket 100 comprises the casing 4, the input line 5, output connectors 7, the selective coupling stage 8 and a switch button 110, outside the casing 4 and removably connected by a cable 111 and a connector 112. In particular, the length of the cable 11.1 is such that the switch 110 can be arranged at a distance from the casing 4. Moreover, in this case, the switch 110 is back-lit by an integrated LED 114. The selective coupling stage 8 is controlled by the switch 110, which is of the normally open type and returns to the home position after it has been pressed. The power required to operate the selective coupling stage 8 in this case is supplied by a power supply unit 113.

As illustrated in figure 4, also in case of the multiple socket 100, the selective coupling stage 8 comprises the relay 15, the triac 16 and a galvanic decoupling device, i.e. the photo-coupling device 17.

The power supply unit 113 is connected to the input line 5 upstream of the relay 15 and supplies a safety voltage V₃ for example of 12 V. to the output terminals 113a. The control terminals 16a of the triac 16 are connected to the power supply unit 113 via the photo- coupling device 17 and, selectively when closed, via the switch 110. More specifically, the switch 110 has a first terminal connected to the power supply unit 113 for receiving the safety voltage V₃ and a second terminal connected to the photo-coupling device 17, which is in turn connected to the control terminals 16a of the triac 16. Furthermore, the power supply unit 113 permanently supplies the safety voltage V_s to the LED 114 of the switch 110. Also in this case, when the switch 110 is operated it activates the triac in order to send a pulse to the coil 15a so that the relay 15 switches . Thus when the switch 110 is operated the output terminals of the multiple socket 100 and the power main 3 are alternately coupled and decoupled.

Figure 5 shows a third embodiment of the invention. In this case, a multiple socket 200 comprises the casing 4, the input line 5, output connectors 7, a selective coupling stage 208 and a switch button 210, outside the casing 4 and removably connected by a cable 211 and a connector 212. In particular, the length of the cable 211 is such that the switch 210 can be arranged at a distance from the casing 4. A fuse 209 is arranged along one of the conductors of the input line 5. The switch 210 is backlit by an integrated LED 214. The selective coupling stage 208 is controlled by the switch 210, which is of the normally open type and returns to the home position after it has been pressed. The power required to activate the selective coupling stage 8 in this case is supplied by a power supply unit 213, housed inside the casing 4, which supplies a safety supply voltage V_s for example of 12 V.

The selective coupling stage 208 comprises two relays 215, a control circuit 216 and a drive circuit 217. The relays 215 have first conduction terminals 215b connected to respective conductors of the input line 5 and second conduction terminals 215c connected to the output connectors 7. Furthermore, the relays 215, which are of the conventional type, comprise coils 215a, which control respective contacts 215d. The coils 215a are of the low control voltage type, for example 12 V, and each has a first control terminal 215e, connected to the power supply unit 213, and a second control terminal 215f connected to a respective output of the drive circuit 217. The control circuit 216, which may be of the analog or numerical type, is a bistable circuit having input terminals 216a connected to respective outputs of the power supply unit 213 and output terminals 216b connected to respective inputs of the drive circuit 217. ^' Furthermore, the control circuit 216 has two control terminals 216c connected to the power supply unit 213, one directly and the other via the switch 210, selectively when closed. More specifically, the switch 210 has a first terminal connected to the power supply unit 213 to receive the safety voltage V_s and a second terminal connected to the control circuit 216. In a first state (conducting) , the input terminals 216a of the control circuit 216 are connected to respective output terminals 216b and thus the drive circuit 217 and the coils 215a of the relays 215 are coupled to the power supply unit 213 to receive the safety voltage V₃.

In a second state (cut-off) , the input terminals 216a of the control circuit 216 are disconnected from the respective output terminals 216b and the drive circuit 217 and the coils 215a are therefore uncoupled from the power supply unit 213.

The control circuit 216 switches alternately between the first and the second state each time the switch 210 is closed. Therefore, the relays 215 also switch when the switch 210 is operated, making it possible to couple and decouple the output connectors 7 of the multiple socket 200 and the power main 3.

The drive circuit 217 operates in such a way that the two relays 215 switch in response to the operation of the switch 210, not simultaneously, but with a delay in relation to one another. In practice, the contacts 215d are always opened or closed with a delay in relation to one another, which avoids the possibility of disturbance and malfunctioning of the equipment connected to the output terminals of the multiple socket 200. The embodiment in figure 6, which shows a multiple socket 300, differs from the embodiment in figure 5 in that a switch 310 is connected between the power supply unit 213 and the drive stage 217. In this case, the switch 310 has two stable positions and does not return to the home position when released by the user. In the selective coupling stage 308 of the multiple socket 300, the control circuit 216 shown in figure 5 is not therefore necessary. Finally, it is clear that modifications and variations may be made to the electric socket described herein without departing from the scope of the present invention, as described in the appended claims.

In particular, the device according to the invention may be provided with any number of output terminals (even with only one terminal, in case of a single socket) .

Furthermore, the selective coupling stage may include other service components or components for implementing additional functions.

Claims

1. Electric socket comprising: a casing (4) ; an input line (5) , connectable to a terminal (2) of an electric power main (3) ; at least one output connector (7); and a selective coupling stage (8; 208), for selectively coupling and decoupling the output connector (7) and the input line (5) ; characterized in that it comprises a power supply source (13; 113; 213) and a switch (10; 110; 210) for selectively connecting the power supply source (13; 113; 213) to a control terminal (16a; 216c) of the selective coupling stage (8; 208), wherein the switch (10; 110; 210; 310) is arranged outside the casing (4).

2. Socket according to claim 1, wherein the power supply source (13; 113; 213) supplies a safety voltage (V₃) that is lower than a line voltage (V_N) supplied by the power main (3 ) .

3. Socket according to any one of the previous claims, wherein the power supply source (13) comprises a battery.

4. Socket according to any one of the claims from 1 to 3, wherein the power supply source (113; 213) comprises a power supply unit.

5. Socket according to any one of the previous claims, wherein the switch is connected to the selective coupling stage (8; 208) by a cable (11; 111; 211) and a connector (12; 112; 212).

6. Socket according to any one of the previous claims, wherein the switch (10; 110; 210; 310) is a switch button.

7. Socket according to any of the previous claims, wherein the selective coupling stage (8; 208) comprises a relay (15; 215) having first conduction terminals (15b; 215b) connected to the input line (5) and second conduction terminals (15b; 215c) connected to the output connector (7 ) .

8. Socket according to claim 7, comprising a control device (16, 17; 216, 217) for switching a state of the relay (15; 215) in response to the operation of the switch (10; 110; 210; 310).

9. Socket according to claim 8 , wherein the relay (15) is of the impulse type and the control device (16) comprises a triac having conduction terminals connected to the input line (5) and to a coil (5) of the relay (15) and a control terminal (16a) connected to the switch (10) .

10. Socket according to claim 9, comprising a galvanic decoupling device (17) between the switch (10; 110) and the control device (16) .

11. Socket according to claim 8, wherein the selective coupling stage (8; 208) comprises two relays (215) , having input terminals (215b) connected to respective conductors of the input line (5) and output terminals (216c) connected to the connector (7) , and wherein the control device (216, 217) comprises a drive circuit (217), operating in such a way that, when the switch (210; 310) is operated, the relays switch between a cut-off state and a conducting state with a delay in relation to one another.