EP2454746A1

EP2454746A1 - First-fail-safe electromotive furniture drive

Info

Publication number: EP2454746A1
Application number: EP10734966A
Authority: EP
Inventors: Armin Hille
Original assignee: Dewert Antriebs und Systemtechnik GmbH and Co KG
Current assignee: Dewertokin GmbH
Priority date: 2009-07-14
Filing date: 2010-07-14
Publication date: 2012-05-23
Anticipated expiration: 2030-07-14
Also published as: EP2454747B1; CN102498537A; CN102484017B; EP2454746B1; WO2011006931A1; DK2454746T3; AU2010272519B2; US8981679B2; US20120194106A1; US9230764B2; JP2012533161A; US20120206070A1; WO2011006930A1; DE202009005020U1; AU2010272519A1; JP5615358B2; JP5896899B2; CN102484017A; JP2012533283A; EP2454747A1

Abstract

A first-fail-safe electromotive furniture drive (1) is disclosed that comprises at least one drive unit (4) having at least one motor (4.1); at least one actuation device (2) having at least two actuation units (12, 13), each of which includes a motor contact element (12.1; 13.1) and a safety contact element (12.2; 13.2); at least one supply unit (3); and at least one safety device (9). The furniture drive (1) is equipped with an indication device (10) for displaying the functioning and a failure of the at least two actuation units (12, 13) and the safety device (9). The furniture drive (1) includes at least one safety actuation device (25).

Description

First-fail safe electromotive furniture drive

The invention relates to a first-fail safe eiektromic furniture drive GE measure the preamble of claim 1.

Such electromotive furniture drives are known in different versions for the adjustment of various furniture. These furniture includes, among other things, lying and seating furniture, such as beds, slatted frames, TV armchairs. In particular, in the field of home and clinical care as well as in medicine electromotive furniture drives in associated furniture, for example, nursing beds and hospital beds used. These areas of application are subject to relevant regulations, standards and laws with regard to safety, whereby the so-called first fault safety is of great importance

First failure safety means that when a first fault occurs, for example a component, there is no danger to the user and no unwanted and / or unintentional functions and / or unintentional movements of mobile furniture elements are generated which create dangers.

EP 1 341 201 A2 describes an electromotive Verstelianordnung for furniture with a release relay, via whose contacts a total motor current flows, which is then fed to a further relay arrangement for acting on a drive motor to effect an adjustment function. This release unit is assigned a function monitoring module which controls the functionality of the release relay.

DE 103 41 705 A1 describes an arrangement for operating an electrically adjustable sitting and / or lying furniture with a device for supply current-free circuit with a relay. The arrangement comprises a switching gear for switching a motor and a further switching means for switching the relay for supply current release, wherein the switching means of independent switch contacts, which are simultaneously actuated. The object of the present invention is therefore to provide an improved first-fail-safe electromotive furniture drive. The object is achieved by a furniture drive with the Merkmaien of the characterizing part of claim 1. Accordingly, a first-fail safe electromotive furniture drive is provided, comprising: at least one drive unit with at least one motor; at least one actuating device having at least two actuating units, each having a motor contact element and a safety contact element; at least one supply unit; and at least one safety device. The furniture drive is designed with a signaling device for displaying the function and for displaying the at least two actuating units and the safety device.

Further advantageous embodiments are the subject of dependent claims and will become apparent from the following description.

This is a first-fail safe electromotive furniture drive, for example, for use in the medical and / or care sector with requirements for Erstfehlersicherheit provided. The message device not only reports correct functions of functional units, but also an occurrence of errors in these. In this case, not only a functional and error display of safety devices but also of actuators in an advantageously simple manner created.

Another advantage is that even furniture drives with so-called direct circuit are included in the field of application of the invention. Direct switching means that the motor current of the drive motor flows directly through the actuator, with their switching contacts for a high motor current (for example in the range 1 to 10 A) as opposed to a low control current (for example in the range of a few mA to 0.5 A) ) are designed for a Retaisschaltung. Such drives with Direktschaitung are located, for example, in the low price sector, the invention in a simple structure and thus also cost effective for this purpose is used. Of course, it may also be possible for the scope of the invention to include controls that include switching amplifier devices, such as relays, solid state switches, and the like, which are driven by a low control current and switch high motor current. In this case, only the low control current flows through the actuator. Combinations are possible, of course. It is envisaged that the respective one motor contact element and one safety contact element are mechanically coupled to one another. In this case, this coupling can be designed such that one of the contact elements can be actuated in advance. A simultaneous operation is of course also possible.

The safety contact elements of the actuating units switch in coupling with the at least one safety device whose safety switching element. They can therefore be designed for a low control current. In a further embodiment, the safety device is arranged in the actuating device. In this case, the safety switching element of the safety device can be a relay and / or a semiconductor switch. The safety device can also be arranged in the supply unit, the voltage source and / or combined in these. In this case, the combined arrangement means that components of the safety device are placed at different locations, for example in the supply unit and in the voltage source.

An alternative embodiment provides that the safety contact elements of the at least two actuating units form the at least one roofing device. The safety contact elements are designed for the high motor current and connected in series with the associated motor contact elements. Here, there is the advantage that a safety switching element in the form of an additional relay or Halbieiterschalters can be omitted. In addition, a housing of the supply unit can be smaller. Of course, the safety contact elements can also be designed as a semiconductor switch with control contact elements.

The signaling device may have optical and / or acoustic signaling elements. It is also possible to use haptic detectors. It is also conceivable that a device for forwarding messages to external display or monitoring devices is provided. In this case, the forwarding, for example, wired, for example, via the telephone network, electricity or the Internet, done. A wireless forwarding of messages, for example via WLAN or wireless networks, is of course possible. The signaling device may preferably comprise light-emitting diodes as optical signaling elements. In this case, at least one diode unit can be used to save components, or to make logic operations in a simple manner. Nature- lent, it is also possible to ciass logic operations of certain states on Stromieitungen by an evaluation, such as diode gate, diode logic, logic gates, controllers or the like., Are evaluated, the results are then passed to the output by the reporting elements to this.

In a further embodiment, the signaling device has at least one light-emitting diode with a high-impedance resistor. This makes it possible in a simple manner that a current flowing through the internal resistance of the motor low current to detect a first error can be scanned by the reporting device.

In another embodiment, the safety device is part of a power supply unit with auxiliary voltage source. This auxiliary voltage source may be a battery or accumulator, e.g. also with a corresponding charging circuit, or even a mains-connected auxiliary voltage transformer. An auxiliary voltage transformer eliminates the need for battery replacement.

In an alternative embodiment, the first fail-safe electromotive furniture drive comprises: at least one drive unit with at least one motor; at least one actuating device having at least two actuating units, each having a motor contact element; at least one supply unit; and at least one safety device, wherein the furniture drive has at least one safety actuating device.

The safety control ensures safe switching on and off by deliberately activating more than one push-button / switch.

In a preferred embodiment, the actuating device has the safety actuating device. The furniture drive can be configured with a signaling device for displaying the function and for displaying the error of the at least two actuating units and the safety device, and

The at least one safety actuating device may have at least one first main safety contact element, with which it is mechanically coupled, and the switching contacts of the first main safety contact element may be used as electrical Romechanical contacts to influence the state of the safety device to be formed.

In one embodiment, the at least one first main safety contact element is coupled to the safety device via a control block. Thereby, clear control states are possible, namely in that the control block has an ON operating state and an OFF operating state.

The control block can be switched to the ON operating state and the OFF operating state by the at least one first main safety contact element.

Alternatively or additionally, the control block can be switched by a time delay block by means of a predeterminable time delay from the ON operating state to the OFF operating state.

A self-holding state of the safety device can also be formed by a time delay block with a predeterminable time delay. This enables automatic switching off of the safety device. The at least one Sicherheitsbetättgungseinrichtung may have in a further embodiment, at least a second main safety contact element with which it is mechanically coupled, and the Schaitkontakte the second main safety contact element may be formed as eiektromechanische contacts for influencing the state of the safety device.

The at least one first main safety contact element and the at least one second main safety contact element together with the safety device can form a self-retaining device, which is simple in construction and allows a small number of parts.

This Selbsthaiteschaltung can also be formed by a time delay block with a predeterminable time delay. Thus, the time delay block can perform multiple tasks and reduce the number of times. In yet another alternative embodiment, the at least one safety actuation device may comprise at least a third main safety contact element, with which it is mechanically coupled, and the switching contacts of the third Main safety contact element can be designed as electromechanical contacts for influencing the state of the safety device, wherein the third Hauptsicherheitskontakteiement is designed as a detent switch, rotary switch or slide switch. Thus a clearly recognizable switch-on or switch-off state of the safety device can be recognized. In addition, functions can be disabled if this third main security contact element is a key switch, for example.

The invention will now be explained in more detail by means of exemplary embodiments with reference to the accompanying drawings. Hereby show:

Fig. 1 is a schematic block diagram of a first embodiment of a furniture drive according to the invention; Fig. 2 is a circuit diagram of the first Ausführungsbeäspiels of Fig. 1;

Fig. 3 is a circuit diagram of a second Ausführungsbeispieis of the furniture drive according to the invention; Fig. 4 is a circuit diagram of a third embodiment of the invention

Furniture drive;

Fig. 5 is a circuit diagram of a fourth embodiment of the invention

Furniture drive;

Fig. 6 is a circuit diagram of a fifth embodiment of the invention

Furniture drive;

7 is a circuit diagram of a sixth embodiment of the inventive furniture drive;

Fig. 8 is a circuit diagram of a seventh Ausführungsbeispieis of the invention

MöbeSantriebs; and FIG. 9 is a circuit diagram of an eighth embodiment of the invention

Furniture drive. Components and functional elements or groups, which have the same or similar functions, are provided with the same reference numerals in the figures.

1 shows a schematic block diagram of a first exemplary embodiment of an electromotive furniture drive 1 according to the invention.

In this example, the electromotive furniture drive 1 comprises an actuating device 2, a supply unit 3 and a drive unit 4 for adjusting an adjustable part or several of a piece of furniture (not shown).

The supply unit 3 here has a voltage source 8, which is for example a transformer and / or an accumulator. The voltage source 8 can be connected to a Netzanschius 5 to an electrical supply network. Furthermore, the supply unit 3 is here equipped with a safety device 9 for the first fault safety of the electromotive furniture drive 1, which will be explained in more detail below. The Netzanschius 5 can also as a

molded, attached and / or plug-in connector portion may be attached to the housing of the supply unit 3 (for example, as a plug-in power supply). The actuating device 2 is connected via a connecting line 6 to the supply unit 3 via a distributor 18, for example a T-distributor. At this distributor 18 and the drive unit 4 is connected via a motor line 7, wherein this is continued here in the actuator 2. It is also possible in other embodiments that the distributor 18 is located on or in the supply unit 3. In such a case, the connecting line 6 also includes the motor line 7. The distributor 18 may, for example, also be connected to or inserted in the drive unit.

The actuating device 2 here has two first actuating units 12 and two second actuating units 13 for actuating in each case one drive unit 4. In this example, only one group 12, 13 is used, since only one drive unit 4 is present. Of course, more than two drive units 4 can be used, in which case a correspondingly adapted actuator 2 is used and further actuation units 12, 13 has.

The furniture drive 1 is designed such that the motor current flowing through the motor line 7 of the drive unit 4 is supplied from the supply unit 3 to the actuating unit 3. direction 2 is passed, where it can be fed by the actuatable actuators 12, 13 in a corresponding polarity to supply the drive unit 8 in the motor line 7. This is a so-called directly actuated furniture drive 1.

In addition, the actuating device 2 is provided with a signaling device 10, which serves both to display the function and to display a first error and thus the first error security. The reporting device 10 may be executed optically and / or acoustically. Here it has three optical signaling elements 11, which will be described in more detail below.

A circuit diagram of this first embodiment of FIG. 1 is shown in Fig. 2. For simplicity, the manifold 18 is not shown, but is easy to imagine. The supply unit 3 here has a transformer 8.1 as Spannungsqueile 8, wherein a primary winding of the transformer 8 via a Prämärsicherung 22, for example, a thermal fuse in the primary winding, is connected to the power line 5, and wherein a secondary winding of the transformer 8 via a resettable fuse element 21 is connected to a rectifier bridge 19 for the provision of DC voltage. The primary fuse 22 and / or the fuse element 21 can also be assigned in each case additionally a fuse. Primary fuse 22 and / or fuse element 21 can also be only fuses themselves. The rectifier bridge 19 is followed by a smoothing capacitor 20. The negative pole of this DC voltage is connected to a main minus line 6.1 of the connecting line 6. To the positive pole of

Rectifier bridge 19 is a Hauptplusieitung 6.2 of the connecting line 6 connected. Furthermore, the positive pole is connected to a first safety switch contact 15.1 of a safety switch element 15, for example a relay. This first safety switching contact 15.1 is open when the safety switching element 15 is not energized. A closing contact terminal of the first Sachsheitsschalt- contact 15.1 leads to a motor plus 6.3, and a control input of the safety switching element 15, here the winding of the relay is connected to a control line 6.4 of the connecting line 6. Furthermore, the safety switching element 15 is connected to the negative pole (Hauptminusiθitung 6.1) of the secondary DC voltage. The sächheitsschaltelement 15 forms here the safety device. 9 These lines 6.1 to 6.4 lead as connecting line 6 to the actuator 2, with the actuator units 12, 13, they are connected, as will be explained below. The actuating device 2 - also referred to as a so-called manual switch - comprises here the first actuating unit 12 and the second actuating unit 13. In this example, the actuating unit 12 is a button with an actuating button which acts on two contact elements, namely a first motor contact element 12.1 and a first safety contact element 12.2. The first motor contact element 12.1 is a changeover contact and the first safety contact element 12.2 is designed as a make contact. In the same way, the second actuating unit 13 is constructed with a second motor contact element 13.1 (changeover contact) and a second safety contact element 13.2 (normally open contact). By a respective actuating button (not shown), the motor contact elements 12.1 and 13.1 and the safety contact elements 12.2 and 13.2 are actuated together. These

Operability can be designed such that either both contact elements 12.1 / 12.2 and 13.1 / 13.2 can be actuated simultaneously or in succession. In the latter case, first the safety contact element 12.2 / 13.2 is actuated ("leading contact element") and then the motor contact element 12.1 / 13.1 is reversed when it is released, both contact elements 12.1 / 12.2 and 13.1 / 13.2 can each have, for example, a common actuating element, However, they can also be actuated simultaneously or one after the other by a type of rocker, whereby only one press of a button is required. to effect a movement of the drive unit 4.

The contact elements 12.2., 13.2 can also be designed so that they have a switching output, which consists for example of a semiconductor switch or relay switching contact, which is controlled by a certain size, such as a touch switch, proximity switch, touch screen u. like.

The respective changeover contact of the motor contact elements 12.1 / 13.1 is connected in each case with its connection a via the motor line 7 to a motor 4.1 of the drive unit 4. In idle state, each changeover contact connects the connection a with a normally closed contact b. When actuated, each changeover contact connects the connection a with a normally open connection c. The Öffneranschlüsse b are each with connected to the Hauptminusieitung 6.1 and the normally open terminals c are each connected to the Motorpiusleitung 6.3. The safety contact elements 12.2 and 13.2 are each connected to a connection d with the control line 6.4 and are each connected to a terminal e to the main positive line 6.2.

In addition, the Betättgungseinrichtung 2 is equipped with the annunciator 10, which here comprises three indicator lights 11.1, 11.2 and 11.3 in the form of light emitting diodes (LED) with respective series resistors R1, R2 and R3. The first indicator light 11.1 is here connected via series resistor R1 to the control line 6.4 and to the main minus line 6.1, the cathode of the LED lying on the main minus line 6.1. The second indicator light 11.2 is connected to the cathode via the series resistor R2 to the main negative lead 6.1 and with its anode to the motor plus 6.3. The third indicator light 11.3 is connected with its anode via the series resistor R3 to the main positive line 6,2 and with its cathode to the motor plus line 6.3.

If this first or the second actuating unit 12, 13 is actuated in order to switch the motor 4.1 in a corresponding direction of movement, then the respective safety contact element 12.2, 13.2 switches on the safety switching element 15 whose safety contact 15.1 connects the main axis 6.2 to the motor axis 6.3. Thus, the normally open terminals b of the motor contact elements 12.1, 13.1 are at the potential of the main positive line 6.2, the motor 4.1 is switched on accordingly and the first indicator light 11.1 lights up as long as the respective safety contact element 12.2, 13.2 is actuated. It signals its function. When you release the depressed actuator unit 12, 13, the first indicator light must go out 11.1. If this is not the case, it signals a first error, namely that the actuated safety contact element 12.2, 13.2 has not switched off. If it does not shine at all, it signals that the actuated safety contact element 12.2, 13.2 has no function. Indicator light 11.1 thus serves for the function display and error display of the safety contact elements 12.2, 13.2 and thus contributes to the first-fault safety.

As soon as the motor positive line 6.3 is at the potential of the main positive line 6.2, the second indicator light 11.2 lights up. It thus serves to display the function of the safety switching element 15. If, despite actuated safety contact element 12.2, 13.2 and its respective correct function display, it does not light up so clearly. The second display light 11.2 siert a first error of the Sicherheitsschaitele- element 15 and also contributes to Erstfehlersicherheit.

The series resistor R3 of the third indicator light 11.3 is particularly high impedance. The third indicator light 11.3 signals a faulty motor contact element 12.1, 13.1 in the case of lights, for example in the event that the closing contact a / c of a respective changer of a motor contact element 12.1, 13.1 is burned or welded and no longer opens. Then lies in the unactuated state of the actuator 2, the motor plus 6.3 via the faulty closed motor contact element 12.1, 13.1, thus connected via the motor line 7 motor 4.1 and the other motor contact element 12.1, 13.1 on the main minus 6.1 (via the Snnenwiderstand of the motor 4.1). In this way, then the third indicator light 11.3 turned on and thus indicates this first error. The current flowing through the motor is so low that the motor does not start.

3 illustrates a circuit diagram of a second embodiment of the furniture drive 1 according to the invention, wherein in contrast to the first embodiment shown in FIG. 2, the safety switching element 15 is arranged in one of the voltage source 8 to the power supply 5 upstream power switching unit 16 and a second Sicherheitsschaitkontakt 15.2 the voltage source 8 connects to the mains connection upon energization of the safety switching element 15. The saxen switch contact 15.2 is here designed as a bipolar. The safety switching element 15 also forms the safety device 9. The network switching unit 16 is also referred to as mains isolation. Since there is no energy for energizing the safety switching element 15 when the mains connection 5 is disconnected from the voltage source 8, an auxiliary voltage source 17 is arranged with an auxiliary voltage transformer 17.1, which is permanently connected to the mains connection 5. The auxiliary voltage source 17 may also be a battery and / or an accumulator. The auxiliary voltage source 17 supplies a DC voltage (here by bridge rectifier and smoothing capacitor) whose negative Po! with the safety schaitelement 15, the cathode of the LED of the second indicator light 11.2, which is here in the Netzschaiteinheit 16 is arranged (but can also be arranged in the actuator 2), and an auxiliary negative lead 6.5 of the connecting line 6 is connected. The positive pole of the auxiliary voltage source 17 is connected via an auxiliary positive line 6.6 to the main positive line 6.2 of the connecting line 6. Thus, the main positive line 6.2 always carries the potential of the auxiliary positive line 6.6. The safety switching element 15 is connected to a field connection or control Finally connected to the control line 6.4. A motor plus 6.3 is not present, since the Hauptpiusleitung 6.2 and the main minus 6.1 by the safety switching element 15 are switchable. The actuator units 12, 13 of the actuator 2 are constructed as in the first embodiment. Their connections to the connection cable 6 are as follows. The terminals a of the motor contact elements 12.1, 13.1 are connected to the motor line 7 (as in FIG. 2). The terminals b are also located on the main minus lead 6.1 as in the first embodiment. But the connections c are connected to the main positive line 6.2. The terminals d of the safety contact elements 12.2, 13.2 are together on the control line 6.4, and the terminals e are connected to the main positive line 6.2 and the auxiliary positive line 6.6.

When an actuating unit 12, 13 is actuated, a respective safety contact element 12.2, 13.2 switches on the safety switching element 15, which connects the voltage source 8 to the mains connection 5, by virtue of the potential of the auxiliary positive line 6.6 on the main axis 6.2. Then the main positive line 6.2 leads the potential of the voltage source 8, which is switched by the respective actuated motor contact element 12.1, 12.2 on the motor 4.1 for the movement thereof.

The first indicator light 11.1 (indicator light designed as an LED) is connected in this second exemplary embodiment with the cathode to the main minus lead 6.1 and the anode via the dropping resistor R1 to the main positive lead 6.2. It lights up when the safety switch element 15 is turned on when actuated. If it does not light when actuated, this is a signaling of a first fault of the safety switching element 15.

The second indicator light 11.2 also lights up when actuated and indicates a defective safety contact element 12.2, 13.2 when actuated by non-lighting.

The third indicator light 11.3 is connected via a diode unit 14, which is connected between the motor lines 7, connected to the anode via a series resistor R4, wherein its cathode is connected to the auxiliary negative lead 6.5. The

Diode unit 14 has a first diode 14.1 and a second diode 14.2, whose cathodes are connected together, and whose anodes are each connected to a motor line 7. The cathodes are connected to the third indicator light 11.3. When the engine is switched on 4.1, that is, when pressed, the third indicator light 11.3. If it does not light despite being actuated, it signals a first fault of a motor contact element. If it lights up after releasing an actuating unit 12, 13, it signals, for example, a glued shooting contact a / c of a previously actuated motor contact element 12.1, 13.1.

Fig. 4 shows a third embodiment of the furniture drive 1 according to the invention, wherein an advantageous simple construction of a first fail-safe furniture drive 1 is provided with direct circuit. In contrast to the first and second exemplary embodiments, the connecting line 6 has only the main minus line 6.1 and the main positive line 6.2, which are supplied by the voltage source 8 (described in FIG. 2).

Another difference to the first and second embodiments is that the safety device 9 is formed in each case by a safety contact element 12.2, 13.2 of the actuating units 12, 13.

While in the first and second Ausführungsbeäspiel the motor current of the motor 4.1 via the motor contact elements 12.1, 13.1 flows and the safety contact elements 12.2, 13.2 are acted upon only with a control current for the safety switching element 15, in the third embodiment, the safety contact elements 12.2, 13.2 acted upon by the motor current, since they are connected in series with the closing contact a / c of the respectively associated motor contact element 12.1, 13.1. In this case, the connections a are connected to the main line 6.1 as in the first and second exemplary embodiments with the motor line 7 and the normally closed connections b. The normally open terminals c of the motor contact elements 12.1, 13.1 are respectively connected to the terminals d of the associated safety contact elements 12.2, 13.2 whose normally open terminals e are in turn connected to the main positive line 6.2.

The first indicator light 11.1 (LED) lies with its cathode at the anode of a series-connected third diode 14.3 of a diode unit 14, whose cathode is connected both to the terminal d of the first safety contact element 12.2 and to the terminal d of the second safety contact element 13.2 , The anode of the first indicator light 11.1 is located at half the supply voltage via a high-impedance voltage divider (R5, R6), which is connected between the main minus 6.1 and the main positive line 6.2. The second indicator light 11.2 (LED) lies with its anode at the cathode of a diode connected in series with the fourth diode 14.3 of the diode unit 14, whose anode is connected to both the Anschus d of the first safety contact element 12.2 and at the Anschiuss d of the second safety contact element 13.2 , The cathode of the first indicator light 11.1 is also at half supply voltage to the high-impedance voltage divider (R5, R6).

Upon actuation of an actuating unit 12, 13, the second indicator light 11.2 lights to check the function as long as the actuation lasts. If a motor contact element 12.1, 13.1 defective (closer a / c glued, welded or the like), so after releasing the operation on the internal resistance of the motor 4.1 negative potential at the cathode of the third diode 14.3, whereby the first indicator light 11, 1 on this Way this first error of a motor contact element 12.1, 13.1 signals. If a safety contact element 12.2, 13.2 (closer d / e squeezed, welded or the like), so after releasing the operation is positive potential of the main positive line 6.2 on the closed contact at the anode of the fourth diode 14.4. Then the second indicator light 11.2 lights and signals this first error of a safety contact element 12.2, 13.2 in this way. The current flowing through the motor in this case is so low that a breakaway torque for starting the engine is not generated, and the motor thus does not move.

A first fault of the motor contact elements 12.1, 13.1, safety contact elements 12.2, 13.2, safety switch elements 15 and / or safety switch contacts 15.1 does not lead to any uncontrolled behavior of the furniture drive and is signaled immediately. This is a first-fail safe electric motor furniture drive 1 created in direct circuit. In Fig. 5 is a circuit diagram of a fourth embodiment of the furniture drive 1 according to the invention is shown.

In this example, the safety switching element 15 is similar to the second Ausführungsbetspiel according to FIG. 3 in one of the Spannungsqueile 8 upstream of the mains connection 5 downstream network switching unit 16 is arranged. In contrast to the second exemplary embodiment, here the auxiliary voltage source 17 is configured, for example, as a battery, rechargeable battery (accumulator) and / or capacitor with high capacity. forms. A positive terminal of the Hiifsspannungsquelle 17 is connected via a first protection diode 23 to the Hilfspiusleitung 6.6, wherein the negative pole is connected to the main minus line 6.1. The protective diode 23 serves as a

Reverse polarity protection and on the other hand to protect against the voltage that leads the main positive line 6.2, which is generally higher than the auxiliary voltage. Because in a further difference from the second embodiment, a connection of the main positive line 6.2 via a second protective diode 24 with the Hilfspluslei- 6.6 is executed, the second protective diode 24 is located with its anode to the main positive line 6.2. Thus, the Hüfsplusleitung 6.6 always leads the potential of the auxiliary voltage. If the voltage source 8 is switched on, the auxiliary pseudo line 6.6 leads to the cathode of the first protective diode 23 the potential of the auxiliary voltage and behind the cathode the potential of the main pelius 6.2 reduced by the forward voltage of the second protective diode 24. Also in the fourth embodiment, the cathode of the LED is the second indicator light 11.2 arranged in the network switching unit 16 and connected to the auxiliary minus line 6.5 and the main Minusieitung. As in the second exemplary embodiment, the safety switching element 15 is connected to the exciter connection or control connection to the control line 6.4. Again, a motor plus 6.3 is not present, since the main plus line 6.2 and the main minus 6.1 by the safety switching element 15 are switchable.

The actuators 12, 13 of the actuator 2 are constructed as in the second embodiment. Their connections to the connection cable 6 are as follows. The connections a of the motor contact elements 12.1, 13.1 are connected to the motor line 7 (as in FIGS. 2 and 3). The terminals b are also on the main minus lead 6.1 as in the first and second embodiments, and the leads c are connected to the main positive lead 6.2. The terminals d of the safety contact elements 12.2, 13.2 are located together on the control line 6.4, wherein the terminals e, in contrast to the second embodiment, are connected to the Hilfspiusleitung 6.6.

Upon actuation of an actuation unit 12, 13, a respective safety contact element 12.2, 13.2 switches on the safety switching element 15 through the potential of the auxiliary exciter line 6.6, which connects the voltage source 8 to the mains connection 5. Then leads the Hauptpiusleitung 6.2 the potential of the voltage source 8, which by the respective actuated motor contact element 12.1, 13.1 to the motor 4.1 is switched for its movement. At the same time, the potential of the main protective conductor 6.2 is then applied via the second protective diode 24 to the auxiliary positive conductor 6.6 and conducted to the safety switching element 15 via the respective closed safety contact element 12.2, 13.2. This is advantageous when the auxiliary voltage source 17 has only a small capacity, which is sufficient for switching but not for maintaining an on state of the safety switching element 15. Thus, auxiliary voltage sources 17 can be used with little space. The first indicator light 11.1 (indicator light designed as LED) is connected in this fourth embodiment with the cathode to the main minus lead 6.1 and the anode via the dropping resistor R1 to the main positive lead 6.2. It lights up when the safety switch element 15 is turned on when actuated. If it does not light when actuated, this is a signaling of a first fault of the safety switching element 15.

The second indicator light 11, 2 also lights up when actuated and indicates a defective safety contact element 12.2, 13.2 when actuated by non-lighting. 6 shows a circuit diagram of a fifth exemplary embodiment of the furniture drive 1 according to the invention. In this case, the actuating device 2 has at least one safety actuating device 25 which is mechanically coupled to at least one first main safety contact element 25.1. The switch contacts of the first main safety contact element 25.1 are designed as electromechanical contacts and influence the state or the activity of the safety device 9 by switching the safety switch element 15.1 and / or changing the switch position of the at least one main safety contact element 25.1. In this fifth exemplary embodiment, the at least one main fuse contact element 25. 1 is designed as a make contact and connected to the main positive line 6. 2. Via a control line 6.4, it is connected to a control block 26, which in turn is connected to the safety switching element 15. The control block 26 is here connected to a time delay block 27, which is connected via a signal line 6.8 with the diode unit 14 so that its connection is at the cathode of the first diode 14.1 and the second diode 14.2 The control block 26 also has an auxiliary input 29 for connecting other signal transmitters, for example, an overcurrent shutdown of the engine 4.1, which is not shown.

The main safety switching element 25.1 is connected here as a so-called start button. This start button is pressed before an operation of the engine 4.1. Upon depression of the start button or main fuse contactor 25.1, the control block 26 is switched to an ON-state and in turn switches the safety switch element 15, e.g. a relay as in the first embodiment, a. The safety switching element 15 then connects here the main minus lead 6.1 with an engine minor 6.7. Then can be turned on the actuators 12 and 13 of the engine 4.1 in the desired adjustment. When the motor 4.1 is switched off, a signal is transmitted via the signal line 6.8 to the time delay block 27, which switches the control block 26 back from the ON operating state to an OFF operating state after a predeterminable period of time, wherein the safety switching element 15 is the main minus 6.1 from the motor common 6.7 separates. About the additional control input 29, a reset of the control block 26 is also possible. Another embodiment provides a time delay block 27 which, upon actuation of the actuators 12, 13 after a predetermined period of time, returns the control block 26 from the ESN mode to an OFF mode,

The control block 26 may be provided in a variant not shown with a so-called T-Fiip-flop, which is turned on by the main security switching element 25.1 by a first actuation and turned off by a second operation.

The second indicator light 11.2 signals that the motor minus line 6.7 is under voltage. This means when the main safety switching element 25.1 is switched off, that the safety switching element 15 or the control block 26 has an error.

The third indicator light 11.3 lights up when the motor 4.1 is running or the motor cable is carrying voltage. When not actuated actuation units 12, 13 and still switched safety switch element 15 such an error of the actuator units 12, 13 is signaled by lighting. It is also possible that only the time delay block 27 performs a reset of the control block 26. This is shown in FIG. 7 in a sixth embodiment. Here, the time delay block 27 has a SägnaSaufbereitung 28 which the Signa! the signal line 6.8 already processed when switching on the motor 4.1 so that when switching on (or off) the motor 4.1, the time delay starts. Of course, many other variations of the time delay are conceivable. The fourth indicator light 11.4 here signals the switched-on state of the time delay block 27 and can thus indicate an error of the same by continuous lighting after the end of an operation or non-illumination when the motor 4.1.

According to an embodiment, which shows FIG. 8 as a seventh exemplary embodiment of the furniture drive 1 according to the invention, two main-axis contact elements 25.1 and 25.2 are provided and connected in circuit terms with the at least one safety switching contact K2 of the safety switching element 15 (in this case a relay 15.1) in that the first main safety contact element 25.1 closes the contact of the at least one safety contact K2, while upon actuation of the second main safety contact element 25.2 the at least one safety switching contact 15.2 is opened again. Both main safety contact elements 25.1 and 25.2 are in this case designed as a pushbutton and are connected together with the at least one safety switch contact 15.2 in a self-holding circuit, the first main safety contact element 25.1 activating the self-hold as NO contact and start switch and the at least one safety switch contact K2 coming from its rest position Switches on a switched-on state. This takes place in that the first main safety contact element 25.1 connects the main miniature line 6.1 to the relay 15.1, which via another control line 6.4 ^! and the closed

Normally closed contact of the second main safety contact element 25.2 lies on the main positive line 6.2 and attracts. According to this embodiment, the second main safety contact element 25.2 lifts by pressing the Selbsthaitung of the relay 15.1 again and the at least one safety switch contact K2 goes back to its idle state.

Optionally, the time delay block 27 may additionally or solely form a self-holding via a connecting line 31 with the motor minor line 6.7 and via a connecting diode 30, which is connected to the control line 6.4. When the start button 25.1 is pressed, the safety contact K2 closes, with the time delay 27 via the connecting line 31, the potential of MotorModusieitung 6.7 on the control line 6.4 sets, whereby the relay 15.1 remains energized. At the same time a time delay is initiated, which interrupts this Seϊbsthalte connection after a predeterminable time, whereby the relay 15.1 drops again. The indicator lights 11.2 and 11.3 are already described above.

An eighth embodiment according to FIG. 9 provides a detent switch as a third main safety contact element 25.3, which is designed, for example, as a rotary switch or as a slide switch and has latching switching positions. The contacts of the latching switch are connected to the safety switching element 15 or here with the Reiais 15.1 shown or form the at least one safety switch contact. The detent switch can be operated manually or only with Hinzutun an auxiliary tool, for example in the form of a Codiersteckers or a key in different versions.

The indicator light 11.2 lights up when the safety contact K2 is closed, with the motor plus 6.3 being live. When the motor 4.1 is switched on, the indicator light 11.2 can shine weaker. When the safety contact K2 is opened, the indicator light 11.2 extinguishes.

The indicator light 11.3 indicates by illumination a fault of an actuator 12, 13. When the safety contact K2 is opened, e.g. an adhesive contact of an actuating unit 12, 13 negative potential of the main minus lead 6.1 put over the motor winding of the motor 4.1 to the cathode of the indicator light 11.3 and turn them on, since its cathode is above the resistor R3 to positive potential of the main positive line 6.2.

The invention is not limited to the embodiments described above. It is modifiable within the scope of the appended claims.

Thus, for example, a fourth indicator light a! S supply voltage indicator can be arranged in the actuating device 2, which indicates a defective fuse element 21, 22 at mains connection by non-lighting. The indicator lights 11.1 to 11.3 of the alarm device 10 can also be designed as a multi-color LED. It is also possible, for example, that LEDs with inte- Blink circuit are used, the Bünkfunktion is used for error representation.

It is conceivable that the fuse switching element 15 of the first exemplary embodiment can be arranged in the actuating device 2, the voltage supply being, for example, a plug set. Thus, it is possible to dispense with a separate housing of the supply unit 3.

In the actuator 2 may also be arranged a so-called overcurrent shutdown for switching off an engine in case of overload. Of course, such an overcurrent shutdown can also be arranged, for example, in the supply unit 3 and / or at another suitable location in the course of the power lines, which lead the motor current during operation of the motor. The safety contact element 12.2, 13.2 can also be designed as a changer, whereby it is possible to lock individual drives 4 against each other, if their concealment functions become a danger during simultaneous operation.

It is also conceivable that the actuating device 2 is provided with locking locks or with suitable locking functions, whereby the power supply of the safety contact elements 12.2, 13.2 can be prevented.

Of course, a lighting of the actuator 2, for example with LEDs, possible.

The SicherheitsschalteJement 15 may be a semiconductor switch instead of a relay. Thus, it is conceivable that the safety contact element 12.2 / 13.2 as a safety device 9 in the third embodiment (see FIG. 4) may be a combination of a mechanical NO contact for control and a power semiconductor switch for the motor current.

Of course, the actuator 2 may also be provided with another voltage source in the form of a battery or a rechargeable battery, whereby a so-called Notabsenkungsfunktion is given. Other connections for additional lights, such as a Unterbettbeieuchtung, for example, be provided by means of X-connector in the connecting line 6. A so-called care LED can also be installed in the supply unit 3, whereby a line to the actuator 2 can be saved. This Care LED indicates an error, for example! when you press the control lights up, does not light up, flashes, their color changes u. Like. It is also possible that the reporting elements 11 of the signaling device 10 are controlled by an evaluation unit. This evaluation unit can, for example, as a diode gate (see diode unit 14), logic gates, controllers u. Like. Be formed, soft voltage and / or current states of the different lines evaluates (even with predeterminable setpoints, Sollkonstellationen etc.) compares and as a result, the MeSdeelemente 11 turns on / off, flashing and / or change color.

In one embodiment of the safety contact elements 12.2, 13.2, these have a movable carbon contact, movable metal contact or a movable foil contact, which is mechanically coupled to an actuating unit and is designed to be manually operable. The respective movable contact is in operative connection with a fixed contact, which is inextricably or cohesively in connection as a carbon contact or as a gold-plated contact of a fixed or flexible printed circuit board or film.

The safety device 9 or the signaling device 10 described in the introduction is generally regarded as part of the furniture drive 1, wherein the safety device 9 and / or the signaling device 10 can be arranged in only one component or separate from one another in different components of the furniture drive 1 in a preferred embodiment , Some arrangements are already described in more detail above, in summary, the safety device 9 and / or the device 10 may be integrated in a component of the furniture drive 1, but at least electrically connected to at least one of the components, the components of the furniture drive 1 essentially from the Supply unit 3, the distribution unit 18, the actuator 2 and / or the drive unit 4 is formed or formed. According to a further embodiment, the above-described overcurrent cutoff has an electrical output which is coupled to the safety device 9. In this case, each drive unit 4 may be coupled with an overcurrent shutdown, however, an overcurrent shutdown may also be coupled with a number of drive units 4 or preferably with only one drive unit 4. In the event of an excessive current consumption of the drive unit 4 or in the event of an excessive current output of the supply unit 3, a mechanical fault of the furniture or an electrical and / or a mechanical fault of the furniture drive 1 may be present. The overcurrent cutoff has a current measuring point, eg in the form of a measuring resistor, with a connected threshold value switch and amplifier and recognizes this excessive current flow and sends an electrical signal to the safety device 9 and / or to the reporting device 10. In one embodiment, the bidirectional device 10 electrically coupled to the Care LED described above or formed by the Care LED. In a further embodiment of the safety device 9, this controls a breaker contact. This controlled breaker contact can be designed as an electromechanical relay contact or as an electronic semiconductor contact, wherein the energy supply to the input or the output of the supply unit 3 or the input of a number, all or each drive unit via the contacts or via the semiconductor layers of the controlled interrupt contact is transmitted. Detects the Sächheitseänrichtung 9 a fault, it controls the controlled breaker contact, whereupon open its contacts or non-conductive and interrupt the current flow to the at least one drive unit 4 or minimize. In a further embodiment, the controlled breaker contact is designed as a manually controllable break contact and, according to further embodiments, is integrated in the housing of the actuating device 2 or in a separate housing, which is connected to a cable of the actuating device. The manually controllable interrupter contact is designed as a normally closed contact as a kind of emergency stop switch / button. The controlled breaker contact can be designed as manually reversible, as electrically reversible or irreversible breaker contact. Thus, upon the occurrence and detection of an error, a non-start of the at least one drive unit 4 is ensured. In addition to the types of display described above for the occurrence of an error, the non-startup of a motor 4.2 or an adjustment unit or a drive unit 4 can also be understood as an indication or as an announcement of an error. The initially described embodiment is described as a T-distributor in an embodiment described at the outset. This T-distributor has in the simplest form three electrical connections, which can be designed in the form of cable connections and / or plug-in form in the form of plug-in connections. In this case, a connection to the supply unit 3, a connection to the actuating device 2 and a connection to the Anträebseinheit 4 is electrically connected. According to various further embodiments, the furniture drive 1 can have a plurality of drive units 4 and / or a plurality of supply units 3 and / or a plurality of actuators 2. All drive units 4, supply units 3 and actuators 2 can be electrically connected to each other by only one distributor unit 18. According to another embodiment, a plurality of distributor units 18 are provided which are electrically connected to a number of drive units 4, supply units 3 and actuators 2. The simplest embodiment provides at least one distribution unit 18, which is attached separately or on furniture or on a component of the furniture drive 1 or integrated therein. According to another embodiment, the at least one distributor unit 18 can be arranged in the supply unit 3, in the voltage source 8, in the actuating device 2 or in the drive unit 4. Conversely, this means that in another embodiment, the safety device 9 and / or the reporting device 10 in the supply unit 3, in the power source 8, in the actuator 2 and / or in the drive unit 1 is arranged or electrically connected thereto. As indicated at least initially, the furniture drive 1 can be provided with a plurality of actuating devices 2 in different embodiments. The actuators 2 may be formed as a hand switch or fixedly attached to the furniture panel or only accessible to the nursing staff switching device. At least one actuating device 2 is available to a person to be cared for or ill, while further actuating devices 2 can only be available to the nursing staff since they are arranged, for example, spatially separated from other actuating devices 2 on the furniture. In a further embodiment, a number or all of the actuators 2 may comprise a mechanical and / or an electric lock. Mechanical locking locks are known, which can be electrically switched, for example, by introducing a mechanical key. Electric lock locks are also known which via a keyboard shortcut or by applying, for example, a magnetic key can trigger lock functions.

The supply unit 3 or the voltage source 8 described at the beginning can be designed according to different embodiments as a network-dependent or as a grid-independent supply unit 3. Mains-independent supply units 3 have batteries or accumulators, which may be connected to upstream charging circuits. Mains-dependent supply units 3 have transformers, e.g. with so-called El-core transformers, ring core transformers or electronic transformers in the form of switchgear with a high-frequency transformer. The supply units 3 can be introduced directly into a socket according to different embodiments, may have a sealed housing in another embodiment and be designed as a base unit for placement on the floor and / or as a built-in device for installation in the furniture.

The main security element 25.1 can also be designed as a first fault-proof main switch, the contacts directly switching or interrupting the main minus lead 6.1 and / or the main positive lead 6.2.

LIST OF REFERENCE NUMBERS

1 furniture drive

2 actuating device

3 supply unit

4 drive unit

4.1 engine

5 mains connection

6 connection line

6.1 Main Minus Lead

6.2 Main positive management

6.3 Motor positive conduction

6.4, 6.4 'control line

6.5 auxiliary ministry

6.6 auxiliary positive conduction

6.7 engine lead

6.8 Signal line

7 motor cable

8 voltage source

8.1 main transformer

9 safety device

10 signaling device

11 signaling element

11.1 First indicator light

11.2 Second indicator light

11.3 Third indicator light

12 First operating unit

12.1 First motor contact element

12.2 First safety contact element

13 Second operating unit

13.1 Second motor contact element

13.2 Second safety contact element

14 diode unit

14.1 first diode

14.2 Second diode

14.3 Third diode

14.4 Fourth diode 15 safety switch

15.1 First safety switch contact

15.2 Second safety switch contact

16 mains switching unit

17 auxiliary voltage source

17.1 Auxiliary voltage transformer

18 distribution unit

19 rectifier bridge

20 smoothing capacitor

21 fuse element

22 primary fuse

23 First protective diode

24 second protection diode

25 safety actuation unit

25.1 First main safety contact element

25.2 Second main safety contact element

25.3 Third main security contact element

26 control block

27 time delay block

28 signal conditioning

29 additional control input

30 Third protection diode

31 connection line

a / b normally closed contact

a / c normally open contact

d / e normally open contact

R1 ... 7 resistance

Claims

claims

1. First-fail-safe electromotive furniture drive (1) with:

at least one drive unit (4) with at least one motor (4.1);

at least one actuating device (2) having at least two actuating units (12, 13), each having a motor contact element (12.1; 13.1) and a safety contact element (12.2; 13.2);

at least one supply unit (3); and

at least one safety device (9),

wherein the furniture drive (1) is formed with a signaling device (10) for displaying the function and for displaying the error of the at least two actuating units (12, 13) and the safety device (9).

2. First-fail-safe electromotive furniture drive (1) according to claim 1, characterized in that the motor contact elements (12.1; 13.1) of the at least two actuating units (12, 13) for direct switching of a motor current with the at least one motor (4.1) are connectable.

3. First-inferior electromotive furniture drive (1) according to claim 1 or 2, characterized in that the respective one motor contact element

(12.1; 13.1) and a safety contact element (12.2; 13.2) are mechanically coupled together.

4. First-fail-safe electromotive furniture drive (1) according to claim 3, character- ized in that each of a motor contact element (12.1;

13.1) and a safety contact element (12.2; 13.2) can be actuated simultaneously or in succession.

5. First-fail-safe electromotive furniture drive (1) according to one of the preceding claims, characterized in that the roof contact elements (12.2; 13.2) of the at least two actuator units (12, 13) for actuating a safety shunt element (15) with the at least one safety device (9) are coupled.

6. First-fail-safe electromotive furniture drive (1) according to one of claims 2 to 5, characterized in that the at least one safety device (9) in the actuating device (2), the Versorgungssein- unit (3), the voltage source (8), and / or combined arranged in these.

7. First-fail-safe electromotive furniture drive (1) according to claim 6, character- ized in that the safety contact elements (12.2; 13.2) of the at least two actuation units (12, 13) which form at least one safety device (9).

8. first-fail-safe electromotive furniture drive (1) according to claim 6, character- ized in that the flatness contact elements (12.2; 13.2) in each case with the corresponding motor contact element (12.1; 13.1) are electrically connected in series.

9. Erstfehiersicherer electromotive furniture drive (1) according to one of the preceding claims, characterized in that the signaling device (10) optical and / or acoustic signaling elements (1 1).

10. Erstfehiersicherer electromotive furniture drive (1) according to claim 8, characterized in that the signaling device (10) has light-emitting diodes as optical reporting elements (1 1).

1 1. Erstfehlersächerer electromotive furniture drive (1) according to claim 9, characterized in that the Meldeeänrichtung (10) at least one evaluation unit in the form of at least one logic circuit and / or a controller for controlling control elements (1 1).

12. Erstfehiersicherer electromotive furniture drive (1) according to claim 11, characterized in that the signaling device (10) has at least one diode unit (14) as Auswerteeänheit

13. Erstfehiersicherer electromotive furniture drive (1) according to claim 8 or

9, characterized in that the signaling device (10) has at least one light-emitting diode with a high-impedance resistor (R3, R5, R6).

14. First-fail-safe electromotive furniture drive (1) according to one of the preceding claims, characterized in that the safety insert Direction (9) is part of a Netzschaiteinheit (16) with Hilfsspannungsquel- Ie (17).

15. First-fault-proof electromotive furniture drive (1) according to claim 14, characterized in that the auxiliary voltage source (17) is a network-connected auxiliary voltage transformer (17.1).

16. First-fail-safe electromotive furniture drive (1) according to claim 14, characterized in that the auxiliary voltage source (17) is a battery, a rechargeable battery or / and a capacitor with high capacity,

17. First-fail-safe electromotive furniture drive (1) with:

at least one drive unit (4) with at least one motor (4.1);

at least one actuating device (2) having at least two actuating units (12, 13) each having a motor contact element (12, 1, 13, 1);

at least one supply unit (3); and

at least one safety device (9),

wherein the furniture drive (1) at least one safety actuator

(25).

18. First-fail-safe electromotive furniture drive (1) according to claim 17, characterized in that the at least one actuating device (2) has the safety actuating device (25).

19. First-fail-safe electromotive furniture drive (1) according to claim 17 or

18, characterized in that the at least one safety operation device (25) has at least one first main safety contact element (25.1) with which it is mechanically coupled, and the switch contacts of the first main safety contact element (25.1) as electromechanical contacts for influencing the State of the safety device (9) are formed.

20. First-fail-safe electromotive furniture drive (1) according to claim 19, characterized in that the at least one first main safety con- Clock element (25.1) via a control block (26) is coupled to the safety device (9).

21. First-fail-safe electromotive furniture drive (1) according to claim 20, character- ized in that the control block (26) has an ON operating state and an OFF operating state.

22. First-fail-safe electromotive furniture drive (1) according to claim 21, characterized in that the control block (26) by the at least one first main safety contact element (25.1) in the ON operating state and the OFF operating state is umschaitbar.

23. First-fail-safe electromotive furniture drive (1) according to claim 20 or

21, characterized in that the control block (26) by a Zeitverögerungsbiock (27) by means of a predeterminable time delay from the E! N operating state in the OFF operating state is switchable.

24. First-fail-safe electromotive furniture drive (1) according to one of claims 17 to 19, characterized in that a self-holding state of the safety device (9) by a time delay block (27) is formed with a predeterminable time delay.

25. First-fail-safe electromotive furniture drive (1) according to claim 19, characterized in that the at least one Sicherheitsbetätigungsein- direction (25) at least a second main safety contact element (25.2), with which it is mechanically coupled, and the switch contacts of the second main safety contact element (25.2) as electromechanical contacts for influencing the state of the safety device (9) are formed.

26. First-fail-safe electromotive furniture drive (1) according to claim 25, characterized in that the at least one first main safety contact element (25.1) and the at least one second main safety contact element (25.2) form a self-holding circuit together with the safety device (9).

27. First-fail-safe electromotive furniture drive (1) according to claim 26, characterized in that the self-holding circuit by a Zeitverzö- gerungskoock (27) is formed with a predeterminable time delay.

28. First-fail-safe electromotive furniture drive (1) according to claim 17 or

18, characterized in that the at least one safety operation device (25) has at least one third main safety contact element (25.3) with which it is mechanically coupled, and the switch contacts of the third main safety contact element (25.3) as electromechanical contacts to Influencing the state of the SScherheätseinrich- device (9) are formed, wherein the third Hauptsicherheitskontakteiement (25.3) is designed as a detent switch, Drehschaiter or slide switch.

29. Erstfehiersϊcherer electromotive furniture drive (1) according to any of claims to 17 to 28, characterized in that the furniture drive (1) with a meide device (10) for displaying the function and error display of the at least two actuator units (12, 13) and the safety device (9) is formed.