AU2012200445A1 - An off-mains switch and a control box for electrically driven articles of furniture - Google Patents

Abstract

AN OFF-MAINS SWITCH AND A CONTROL BOX FOR ELECTRICALLY DRIVEN ARTICLES OF FURNITURE An off-mains switch (14) and a control box (15) for electrically adjustable articles of furniture, such as beds, chairs or tables, which automatically interrupt the connection to the power supply when the article of furniture is not adjusted, such that this will not constantly be under the mains voltage. These off-main switches require a multi-part cable 10 which is rigid and thick. In the present structure (14, 15) a single two-part cable (13) is sufficient, as the off-mains switch (14) is configured such that the control signals between control unit/control box (15) and the off-mains switch are transmitted through a mains cable (13). A standard cable having two conductors is then sufficient. This means in turn that standard plugs may be used, and thus that the cable (13) may be connected to the is power supply via an ordinary plug. Since, hereby, the off-mains switch may appear as a separate unit, production and logistics are facilitated.

Description

S&F Ref: 874191D1 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address Linak A/S, of Smedevognet 8, Guderup, DK-6430, of Applicant : Nordborg, Denmark Actual Inventor(s): Henning Kristensen Address for Service: Spruson & Ferguson St Martins Tower Level 35 31 Market Street Sydney NSW 2000 (CCN 3710000177) Invention Title: An off-mains switch and a control box for electrically driven articles of furniture The following statement is a full description of this invention, including the best method of performing it known to me/us: 5845c(5927738_1) 1 An off-mains switch for electrically driven articles of furniture This divisional application is related to Australian Patent Application No. 5 2007229156, the content of which is incorporated herein by reference in its entirety. The present invention relates to an off-mains switch for use in connection with electrically driven articles of furniture. 10 To avoid the situation that an electrically adjustable and/or driven article of furniture, such as a bed, a chair or a table, is constantly supplied with mains voltage to the local transformer of the article of furniture, so-called off-mains switches have been developed, which automatically interrupt the connec 15 tion between the mains supply and the local transformer when the article of furniture is not active, i.e. is not adjusted. The interruption may take place by means of a relay, or a unit having a corresponding relay function, lo cated in the off-mains switch. 20 When the article of furniture is adjusted to perform e.g. a raise function, such as by operation of a functional key on a hand control associated with the article of furniture, or by a separate activation of the off-mains switch via the hand control and/or directly on the off-mains switch, the off-mains switch is activated and establishes the connection to the mains. Such off 25 mains switches are known from EP 0 615 667 B2 Okin, DE 92 12 599.9 U1 Dewert, EP 0 792 532 B1 LINAK as well as WO 2004/019463 Al LINAK. Off-mains switches serve inter alia to prevent or at least reduce the pres ence of electric or magnetic fields, E-fields and H-fields, respectively, in the article of furniture. 30 The off-mains switch of EP 0 615 667 is based on an actuator system, in which the operational voltage to the actuator is also a control voltage. Acti vation of the relay relies on the use of an auxiliary voltage source, coupled 2 in parallel with the main power supply, in the form of a capacitor coupled in for feeding the main power supply, and optionally an additional conductor for earth connection, as well as at least one additional wire having a con ductor for use in the control of the relay in the off-mains switch by means of 5 the control unit, which may result in a strong and inflexible total intermedi ate cable. A special cable, like an intermediate cable, is relatively costly per se, and to avoid special connectors, which may also be relatively costly, the cable is 10 firmly mounted in the off-mains switch as well as in the power supply and the control unit. This is not very expedient in terms of handling and ship ment. In addition, a standard length of the intermediate cable also has to be used, more or less, irrespective of the customer's needs being a shorter or longer cable. 15 A need exists to provide an off-mains switch as well as a control box for an actuator system intended for use for an adjustable article of furniture, which fully or partly solves one or more of the above problems singly or in any combination. 20 A further need exists to provide a structure and a mode of operation for an off-mains switch and a control box, coupled to it, for an actuator system, in which electric and/or magnetic fields at the actuator because of a mains voltage do not exist, and in which it is constantly ensured that energy is 25 present at the actuator for establishing connection of the actuator to the mains voltage. A further need exists to provide a structure of an off-mains switch and a control box for an actuator system, where a single cable having two 30 conductors as an intermediate cable will suffice, that is where the intermediate cable exclusively consists of a cable having two conductors and optionally an additional conductor for an optional earth connection.

3 Summary According to one aspect of the present disclosure, there is provided an off mains switch intended for off-mains switchable actuators for electrically driven articles of furniture, said off-mains switch comprising: an off-mains 5 switch energy input which may be connected to a mains voltage outlet for supplying the off-mains switch energy input with a mains voltage; an off mains switch energy output intended as an output for mains voltage, wherein the off-mains switch energy output is additionally adapted to receive the control signal and pass on the control signal to the control 10 signal receiver; a relay means arranged in an electrical connection path between the off-mains switch energy input and the off-mains switch energy output; and a control signal receiver intended to control the relay means on the basis of the control signal. 15 According to another aspect of the present disclosure, there is provided Other Disclosure When the signals between the control unit and the off-mains switch may be transmitted through a mains cable, a separate conductor for transmitting 20 the control signal is not needed, and a standard mains cable having two electrical conductors as an intermediate cable suffices. This means in turn that a standard plug may be used, and thus the cable may be connected to the power supply via an ordinary plug. Since the off-mains switch may hereby appear as a separate unit, production and logistics will be facilitated. 25 When the control signal applied from the control box to the off-mains switch is used as an indicator of the size of the low energy storage in the control box, a solution is achieved where the off-mains switch and the control box currently exchange information on the size of the energy storage. Hereby, 30 the amount of energy on the low energy storage may be adapted such that enough energy is constantly available for supplying the control signal transmitter - but such that as little energy as possible is transferred to the control box in a passive state.

4 When the size and/or the frequency of the low voltage and thereby the low energy transfer to the low energy storage are changed only when so needed because of declining strength and/or frequency and/or duration of the control signal, a solution is achieved where it is constantly ensured that 5 there is energy in the control box during "passive mode" for applying a con trol signal to the off-mains switch, and where it is ensured at the same time that the amount of low energy being transferred is adapted to this purpose. Special embodiments of the off-mains switch are defined in claims 2 - 21. 10 The off-mains switch could be configured in connection with a control box intended for off-mains switchable drives for electrically driven articles of furniture, said control box comprising, a control box energy input, and a control signal generator for applying a control signal for controlling the energy to the control box energy input, and wherein the control box energy 15 input is adapted to apply the control signal from the control signal generator. In this connection the control box could additionally comprise a low energy storage for supplying the control signal generator with energy, when the 20 control box does not receive mains supply on the control box energy input. Further, the control box could additionally comprise a mains transformer having a primary winding and a secondary winding, wherein a first pole and a second pole on the primary winding are electrically connected to a first 25 electrical conductor and a second electrical conductor on the control box energy input, and wherein the low energy storage receives low energy by drawing energy from a voltage increase on the secondary winding. In a still further elaboration of the invention embodied in connection with the 30 control box, the voltage increase on the secondary winding is rectified and used for gradually building-up a supply voltage for generating the control signal.

5 Additionally, the control box could comprise an operating signal input, and wherein the signal generator is adapted not to give a control signal when one or more signals are received from the operating signal input, and to give a control signal when one or more signals are not received from the 5 operating signal input. Moreover, the mains voltage could be received on the control box energy input when a control signal is applied from the signal generator, and so that low energy is received when no control signal is applied from the signal 10 generator. In an elaboration of the invention in an actuator system this comprises an off-mains switch according to any one of claims 1 - 21 and a control box, and wherein said actuator system additionally comprises an actuator 15 having an associated operating unit. The actuator system could, additionally comprises an intermediate cable for providing a single electrical connection between the off-mains switch energy output and the control box energy input, and wherein the 20 intermediate cable only has two electrical conductors. The invention could also be elaborated in connection with a system of furniture, consisting of an actuator system, said system of furniture additionally comprising an electrically adjustable article of furniture whose 25 adjustment may be controlled by the actuator. Additional advantages will appear from the following detailed description. 30 5a The invention will be explained more fully below with reference to the exemplary embodiments shown in the drawings. In the drawings: 5 Fig. 1 shows a mattress support shown with raised backrest and leg rest sections, fig. 2 shows a double actuator, 10 fig. 3 shows a basic diagram of an off-mains switch and a control box and their mutual connection via an intermediate cable, fig. 4 shows a complete functional block diagram of the off-mains switch and the control box, 15 fig. 5 shows a signal transfer block diagram, fig. 6 shows a low energy transfer block diagram 20 6 fig. 7 shows an embodiment in accordance with the invention, and fig. 8 shows a further embodiment in accordance with the invention. 5 The invention will be explained more fully below on the basis of an electri cally adjustable mattress frame for beds. However, it will be appreciated that the invention is not restricted to this. As will appear from fig. 1, the mattress support comprises a frame 1 in 10 which a backrest section 2 and an articulated legrest section 3 and a firm central section between these are mounted. In the frame, a transverse shaft 4 is mounted for the backrest section 2, said shaft 4 having a short arm 5 secured to it. Correspondingly, a shaft 6 with a short arm 7 is provided for the legrest section 3. 15 The movement of the backrest and legrest sections 2, 3 is brought about by a double actuator 16, as shown in fig. 2. Fig. 2 shows an actuator system 17 comprising an off-mains switch 14, shown as a box in broken lines, and an intermediate cable 13 which connects the off-mains switch with the con 20 trol box 15 of the actuator 16. The control box 14 is shown as a box in bro ken lines. The actuator 16 comprises a cabinet 8 with a cover 9 which is displaceable from the ends and gives access to a transverse opening 10 for the shafts 5, 7. A drive associated with the shaft openings is driven by a low volt DC motor 11, which is provided perpendicularly from the cabinet. The 25 cabinet additionally accommodates a main power supply and an electrical control unit In a control box 15. The actuator is mounted on the mattress support in that the covers 9 are pulled out, and the actuator is moved upwards until the shafts 5, 7 are en 30 gaged with the respective transverse openings 10 and the arms 6, 8 on the shafts are brought into contact with the drives. The covers 9 are closed 7 again, whereby the actuator hangs on the shafts 5, 7. Activation of the drives causes the shafts to rotate, whereby the backrest section and the legrest section, respectively, are raised or lowered. 5 The actuator is controlled in the example shown by a hand control 12 which is connected by a cable with the control unit 15, also called the control box 15. The actuator is connected to mains, e.g. 240 volts AC, by an ordinary 10 mains cable 13 having two conductors as an intermediate cable, via an off mains switch 14, said off-mains switch 14 being mounted in a mains plug box (not shown). The intermediate cable is permanently mounted in the off mains switch 14, while the other end of the intermediate cable 13 is pro vided with an ordinary plug (not shown) for insertion into a gate at the side 15 of the cabinet 8, said gate being connected electrically to the control box 15. Alternatively, the plug is intended for insertion into a gate directly in the control box 15. It is an advantage that the mains cable is not permanently mounted in the actuator. As an example, this provides for the handling of the off-mains switch 14, the control box 15 and/or the actuator 11 in sepa 20 rate units, at lower costs than if e.g. special plugs were to be used. Alterna tively, the intermediate cable 13 may be equipped with a plug (not shown) at both ends. As mentioned, the off-mains switch 14 serves to keep the actuator free of 25 mains voltage, when mains voltage is not needed, i.e. in passive mode, and no adjustment of the bed takes place. This is due to the desire of having an actuator and/or article of furniture which is free of mains voltage and H-field (magnetic field strength and E-field (electric field strength), respectively. 30 The off-mains switch 14 accommodates a relay or relay means 20 (shown and described more fully in figs. 3 - 8), which, controlled by the actuator via 8 the hand control 12, connects mains voltage as needed. A relay 20 is delib erately chosen such that a galvanic separation is established in the off mains switch as long as the actuator is in a passive mode. When mains voltage is required in the actuator, the galvanic separation is moved down 5 to the mains voltage transformer 34 of the actuator (shown and described more fully in figs. 3 - 8). The following overall functionalities, as described more fully with reference to figs. 3 - 8, are provided in the off-mains switch: 10 - The control signal from the control box 15 is transferred via the mains voltage lines 13 as well as the actual mains voltage. This saves two sig nal lines, and the cable 13 between the off-mains switch 14 and the ac tuator 11 becomes thinner and more flexible. Alternatively, a signal line 15 is saved. The number of conductors saved depends on the principle of transfer which is being compared. The principle of transfer concerns the transfer of a control signal for the control of the relay 20 in the off-mains switch 14. Finally, the number of conductors saved also depends on whether additional separate conductors are used for the transfer of low 20 energy. - Low energy transfer through the mains voltage cable 13 is likewise established. In this respect, the transferred low energy supply in the control box 15 of the actuator is separated from the main voltage supply 25 15 to counteract depletion of a battery 35, if any, and/or another local energy supply, such as in a capacitor in the actuator. Fig. 4 shows a more complete block diagram for the provision of the de sired functions. Few functional blocks will necessarily be present in the ac 30 tuator.

9 The following functions are included in the block diagram of the off-mains switch: - 220 VAC/VDC GPSU: Galvanically separate mains voltage for DC con 5 version 30 - VDC/Low energy transmitter 36: Transfers low energy to the actuator via the intermediate cable 13, the mains filter 37 and the transformer 34 - Relay 20: Connection and disconnection of mains voltage to the control 10 box 15 of the actuator and thereby the actuator 11 - Signal receiver/relay logic 26: Control signal identification and relay control - 220 VACNDC PSU 38: Not galvanically separated mains voltage for DC conversion. 15 The following functions are included in the block diagram of the actuator: - Mains filter 37 Mains filter 37 of the actuator - Mains transformer 34 Mains transformer 34 of the actuator 20 - Main PSU Voltage supply of the actuator and processing of the output signal of the transformer - Low energy receiver 32 Receives low energy from the off-mains switch 14 and provides watch functions 25 39 - Signal transmitter 28 Control signal generator/transmitter controlled by watch functions/pP - Battery 35 Battery may be connected 30 - IR, keyboard, display 39 Watch functions to be "called" by user operating unit 12.

10 Control signal transfer In fig. 5, the block functions for control signal exchange are highlighted, which are: signal transmitter 28, signal receiver 26/relay logic 26 and relay 5 20. These functional blocks will be described more fully below. Signal transmitter 28 This functional block is supplied with voltage by either the low energy re 10 ceiver 32 (described more fully in fig. 5) / Aux PSU or by the main PSU battery 35 functional blocks. The signal transmitter 28 is controlled pas sively/actively via a control input and will default be active as long as mains voltage is not needed. 15 When, via the hand control 12, the user requires mains voltage for motor operation, the transmission of the control signal is stopped, which results in a subsequent activation of the relay 20 in the off-mains switch 14. The control signal may be realized as a mean frequency burst signal 40. 20 Burst to save energy, and mean frequency for it to be arranged as far away as possible from motor generated harmonics. Mean frequency means a signal having a given frequency between 50 and 200 kHz, more particularly a signal having a frequency between 100 and 25 150 kHz, more particularly a signal having a frequency between 120 and 140 kHz. To avoid any problems of noise, it may be expedient to adjust the size and the duration of the individual bursts 40. For example, a burst with a power 30 pulse of a size of 10 - 30 milliamperes and a duration of 90 - 110 micro seconds may be expedient.

l1 Signal receiver 26/relay logic This functional block is supplied with voltage by the 220 VAC/VDC GPSU functional block 30 ("galvanically" separated PSU 30) and detects the con 5 trol signal from the signal transmitter. As long as the control signal in the form of a burst 40 is repeated periodically, the relay 20 is not drawn. When the burst control signal is absent sufficiently long, the relay 20 is drawn and mains voltage is supplied to the control box 15 of the actuator and thereby the actuator 16 and a motor 11. There will be a delay from the absence of 10 the control signal from the actuator and until the relay activation, which is determined by a number of absent bursts. This is done to prevent the situa tion to a reasonable degree that failed burst detections cause untimely acti vation of the relay 20. 15 Relay 20 The relay 20 connects and disconnects mains voltage to the control box 15 of the actuator and thereby to the actuator controlled by the signal receiver 26/relay logic functional block. In the first instance, the relay 20 is supplied 20 with voltage by the 220 VAC/VDC GPSU 30 functional block ("galvanically" separated PSU), which just has a limited energy supply. As soon as the relay has switched the switches, the relay is supplied with voltage by the 220 VACNDC PSU 38 functional block ("not galvanically" separated PSU) with a greater energy capacity in the form of both a higher voltage and 25 power. This principle may be abandoned, and it is shown in fig. 8 that the PSU 38 may be omitted. Low energy transfer 30 The block functions of low energy transfer are highlighted in fig. 6, which are: VDC/low energy transmitter 36 and low energy receiver/Aux PSU.

12 Fig. 6 VDCIlow energy transmitter The functional block receives its energy supply from the 220VACVDC GPSU 30 functional block ("galvanically" separated PSU). This PSU 30 5 provides voltage supply for the low energy transfer, which causes strong voltage fluctuations on the voltage supply during the transfer. A voltage supply of e.g. 20 - 30 VDC is supplied through the one set of contacts 19 on the relay via the mains filter to the pole of the one primary 10 winding of the mains transformer in the actuator. Earth connection 31 is effected at intervals through the other set of contacts 21 via the mains filter 37 to the pole 25 of the other primary winding of the mains transformer 34 in the actuator. The earth connection may take place via a switch, a tran sistor or the like shown at 33 and arranged between the earth connection 15 31 and the other set of contacts 21. The duration of the short earth connections is determined by the PSU en ergy supply and the power of the primary winding of the mains transformer. These conditions are predominantly physically decided. 20 Through the short earth connections, energy is supplied to the core of the mains transformer, which may be drawn on the secondary winding 29. Fig. 6 Low energy receiver 32/Aux PSU 25 This functional block rectifies the voltage increases of the secondary wind ing and gradually builds up a voltage which is used as a supply voltage to the signal transmitter and the watch functions 39: IR, keyboard, display. The energy supply of the Aux PSU is low and may thus not be loaded very 30 hard. Therefore, the signal transmitter 28 decides to send bursts instead of a permanent signal.

13 Variable earth connection frequency Realizing that the low energy transfer still causes H- and E-fields, although low, in the control box, a frequency adjustment of the low energy is imple 5 mented in order to minimize the fields: - When the low energy receiver/Aux PSU supply voltage declines, the burst blocks of the control signal will be spaced more in time, which is to cause the VDC/low energy transmitter 28 to increase the frequency of 10 earth connections 31 and thereby to increase the amount of energy which is transferred. Typically, the interval between the individual earth connections is of the order of half a second (0.5 sec) to one second (1 sec) and the duration e.g. about 10 milliseconds. 15 - When the low energy receiver 32/Aux PSU voltage supply increases, the burst blocks of the control signal will be spaced less in time, which is to cause the VDC/low energy transmitter 36 to reduce the frequency of earth connections 31. 20 Thus, the minimum required energy transfer may be achieved, which leads to lowest possible H- and E-fields in the transformer and circuits of the con trol box and thereby the actuator, respectively. The advantages of the off-mains switch 14 may briefly be summarized as 25 follows: Only two conductors in the mains cable 13. In particular, there are only two conductors in the mains cable 13 (also called the intermediate cable 13 herein) for the transfer of both the control signal to the relay 20, low energy 30 transfer, and for the transfer of the mains voltage. In some cases, there may be an additional conductor (not shown) for the transfer of an earth 14 connection (not shown). Galvanically separated mains voltage from the actuator. In particular, the mains voltage is galvanically separated from the actuator when the actuator 5 is in a passive mode. No mains voltage or H- and E-fields when the actuator is in a passive mode. In particular, there is no mains voltage or H- and E-fields, said fields being caused by a mains voltage having a mains frequency when the ac 10 tuator is in a passive mode. Inverted control of the relay means 20, so that no signal gives mains volt age, and signal gives no mains voltage. 15 Galvanically separated low energy is transferred in parallel with relay con tact to the actuator. The relay 20 does not click when low energy is transferred to the actuator. The reason is that the low energy transfer does not take place as a conse 20 quence of the relay 20 for the supply of the mains voltage being connected and disconnected for this purpose. On the other hand, in the periodic earth connection of the low energy or more particularly the low voltage, where the low energy has a significantly lower power and voltage, a smaller switch 33 is used, e.g. a transistor 33. The low energy supply is typically of the order 25 of 20 - 30 VDC. Because of the smaller power and voltage, a much less audible switch 33 may be used, such as a transistor 33, for this purpose. Fig. 7 describes an embodiment in accordance with the invention. The fig ure shows an off-mains switch 14 intended for off-mains switchable actua 30 tors for electrically adjustable articles of furniture (not shown in the figure). The off-mains switch 14 comprises an off-mains switch energy input 18 15 which may be connected to a mains voltage outlet for supplying the off mains switch energy input 18 with a mains voltage, an off-mains energy output 22 intended as an output for mains voltage, a relay means 20 posi tioned in an electrical connection path between the off-mains energy input 5 18 and the off-mains energy output 22, and a control signal receiver 26 in tended to control the relay means 20 on the basis of the control signal, said off-mains switch energy output 22 being additionally adapted to receive the control signal and pass on the control signal to the control signal receiver 26. 10 Fig. 7 shows moreover the control box 15 intended for off-mains switchable actuators for electrically adjustable articles of furniture, said control box 15 comprising a control box energy input 24 and a control signal generator, also called a signal transmitter 28, for applying a control signal for the con 15 trol of energy to the control box energy input 24, said control box energy input 24 being adapted to apply the control signal from the control signal generator 28. The designations and reference numerals used for fig. 7 are also applicable 20 and used for figs. 3 - 6 and 8. Fig. 8 shows an embodiment in accordance with the invention. In the em bodiment shown, the off-mains switch 14 is not provided with the PSU 38, as shown e.g. in fig. 4. Fig. 8 moreover shows that the off-mains switch ad 25 ditionally comprises a control signal filter 41, connected electrically such that the control signals are fully or partly prevented from getting into the mains. The invention has been explained above in connection with an actuator 30 having a drive at each end, where the electrical equipment is incorporated in the actuator. It will be appreciated that the invention may also be used in 16 the cases where the electrical equipment is gathered in a separate control box, which may be divided into two boxes, one for the power supply and one for the control, alternatively control may be incorporated in the actuator. It will likewise be appreciated that the invention may also be used in con 5 nection with single actuators of the type defined in WO 02/29284 Al. The invention may also find application in chairs and beds equipped with an electrically driven massage system, as disclosed e.g. in WO 03/094822 Al.

16a Other Disclosure 22. A control box (15) intended for off-mains switchable drives for electri cally driven articles of furniture, said control box comprising 5 - a control box energy input (24), and - a control signal generator (28) for applying a control signal (40) for con trolling the energy to the control box energy input (24), 10 c h a ra cte ri z e d in that the control box energy input (24) is adapted to apply the control signal (40) from the control signal generator (28). 15 23. A control box according to claim 22, wherein the control box (15) addi tionally comprises a low energy storage for supplying the control signal generator (28) with energy, when the control box does not receive mains supply on the control box energy input. 20 24. A control box according to claims 22 - 23, wherein the control box ad ditionally comprises a mains transformer (34) having a primary winding and a secondary winding (29), wherein a first pole (27) and a second pole (25) on the primary winding are electrically connected to a first electrical con ductor and a second electrical conductor on the control box energy input 25 (24), and wherein the low energy storage receives low energy by drawing energy from a voltage increase on the secondary winding (29). 25. A control box according to claim 24, wherein the voltage increase on the secondary winding (29) is rectified and used for gradually building-up a 30 supply voltage for generating the control signal (40). 26. A control box (15) according to claims 22 - 25, wherein the control box additionally comprises an operating signal input, and wherein the signal generator (28) is adapted not to give a control signal (40) when one or more 16b signals are received from the operating signal input, and to give a control signal (40) when one or more signals are not received from the operating signal input. 5 27. A control box according to claim 26, wherein the control box is ar ranged such that mains voltage is received on the control box energy input when a control signal (40) is applied from the signal generator, and so that low energy is received when no control signal is applied from the signal generator (28). 10 28. An actuator system (17) comprising an off-mains switch (14) according to any one of claims 1 - 21 and a control box (15) according to any one of claims 22 - 27, said actuator system (17) additionally comprising an ac tuator (16) having an associated operating unit (12). 15 29. An actuator system according to claim 28, additionally comprising an intermediate cable (13) for providing a single electrical connection between the off-mains switch energy output (22) and the control box energy input (24), and wherein the intermediate cable (13) just has two electrical con 20 ductors. 30. A system of furniture, consisting of an actuator system (17) according to claim 28, said system of furniture additionally comprising an electrically adjustable article of furniture whose 25 adjustment may be controlled by the actuator.

Claims (22)

1. An off-mains switch intended for off-mains switchable actuators for electrically driven articles of furniture, said off-mains switch comprising 5 an off-mains switch energy input which may be connected to a mains voltage outlet for supplying the off-mains switch energy input with a mains voltage; an off-mains switch energy output intended as an output for 10 mains voltage, wherein the off-mains switch energy output is additionally adapted to receive the control signal and pass on the control signal to the control signal receiver; a relay means arranged in an electrical connection path between the off-mains switch energy input and the off-mains switch energy 15 output; and a control signal receiver intended to control the relay means on the basis of the control signal.

2. An off-mains switch according to claim 1, wherein the off-mains switch 20 energy output is an output having just two electrical conductors.

3. An off-mains switch according to any one of the preceding claims, wherein the off-mains switch is adapted to control the relay means on the basis of the control signal so as to achieve inverted control of the relay 25 means, such that absence of control signal gives mains voltage on the off mains energy output, and control signal gives interruption of mains voltage for the off-mains switch energy output.

4. An off-mains switch according to either claim 1 or 2, wherein the off 30 mains switch is adapted to control the relay means on the basis of the control signal, so that the relay means is kept in one position as long as a control signal is received, and is changed to another position when no 18 control signal is received.

5. An off-mains switch according to any one of the preceding claims, wherein the off-mains switch additionally comprises a low voltage source, 5 and wherein the off-mains switch is additionally adapted to transfer energy from the low voltage source via an external load, which may be connected on the off-mains switch energy output.

6. An off-mains switch according to claim 5, wherein the off-mains switch is 10 adapted to transfer low voltage via the off-mains switch energy output when the relay means is in one or two relay means positions.

7. An off-mains switch according to either claim 5 or 6, wherein the off mains switch is arranged such that a first pole and a second pole of a 15 primary winding on an external mains transformer may be connected to a first conductor and a second conductor, respectively, on the off-mains switch energy output, and wherein the off-mains switch supplies a low energy supply voltage to the first pole through a first connected set of contacts, and performs brief periodic coupling to an earth connection 20 through a second connected set of contacts on the relay means.

8. An off-mains switch according to claim 7, wherein the frequency of the brief periodic earth connections is determined by an energy supply and the power of the primary winding of the mains transformer. 25

9. An off-mains switch according to either claim 7 or 8, wherein a voltage increase of a secondary winding of the external mains transformer is rectified and used for gradually building-up a supply voltage which is used for generating the control signal. 30

10. An off-mains switch according to any one of claims 7 - 9, wherein the off-mains switch additionally contains a connection means, such as a 19 switch or a transistor, and wherein the periodic connection takes place with the connection means to thereby avoid using the relay means for the periodic low energy transfer. 5

11. An off-mains switch according to any one of claims 5 to 10, wherein the low energy source is an AC to DC conversion unit.

12. An off-mains switch according to any one of the preceding claims, wherein the off-mains switch additionally contains a voltage storage in the 10 form of a capacity capacitor for activating the relay.

13. An off-mains switch according to claim 12, wherein the off-mains switch is arranged such that the low energy source according to any one of claims 5 - 12 is used for charging the capacity capacitor. 15

14. An off-mains switch according to any one of claims 5 - 13, wherein the low energy source comprises an oscillator and a resonance circuit cooperating with the oscillator, said oscillator being connected to the mains via a voltage supply with rectification. 20

15. An off-mains switch according to any one of the preceding claims, wherein the control signal is realized as a mean frequency burst signal.

16. An off-mains switch according to any one of the preceding claims, 25 wherein the relay means is not drawn as long as the control signal in the form of burst is repeated periodically, and only when the burst control signal is absent sufficiently long, is the relay means drawn and mains voltage provided on the off-mains switch energy output. 30

17. An off-mains switch according to claim 16, comprising: a delay from the absence of the control signal and until acti vation of the relay means, said delay being determined on the basis of a 20 plurality of absent bursts.

18. An off-mains switch according to any one of claims 1 - 17, wherein the off-mains switch additionally comprises a control signal filter connected 5 electrically so that the control signals are fully or partly prevented from getting into the mains.

19. An off-mains switch according to any one of the preceding claims, wherein presence of absence of the control signal is used for controlling the 10 relay means for optional transfer of mains voltage via the relay means.

20. An off-mains switch according to any one of the preceding claims, wherein a characteristic of one or more pulses or bursts in the control signal is used for controlling an amount, or a timing, or both an amount and a 15 timing, of a low energy release from the off-mains switch energy output.

21. An off-mains switch according to claim 20, wherein said characteristic is selected from the group of said characteristic consisting of: a size; 20 a duration; a frequency.

22. An off-mains switch according to any one of the preceding claims, wherein the off-mains switch is arranged such that only two electrical 25 conductors in the off-mains switch energy output may transfer mains voltage, receive control signals and release low energy. DATED this Twenty-fifth Day of January, 2012 Linak A/S 30 Patent Attorneys for the Applicant SPRUSON & FERGUSON