EP3649896B1 - Electro-motoric drive for furniture and piece of furniture having such a drive - Google Patents

Description

The invention relates to an electromotive furniture drive for adjusting movable furniture parts of functional furniture, having a control device, at least one adjustment drive with an electric motor and at least one evaluation circuit with an input, which can be electrically connected to a sensor attached to the functional furniture and a proximity and / or touch detector forms. The invention also relates to functional furniture with such an electromotive furniture drive.

Such electromotive furniture drives are known and include, for example, a number of adjusting drives, for example linear drives. A linear drive generates a linear movement on an output member and has at least one electric motor, a gear train and the output member, the gear train with the output member being connected downstream of the electric motor. The linear drive and its output member are connected to furniture components and move or adjust these relative to one another when the motors are in operation. The furniture components are movably connected, for example, to a base frame and / or to each other by so-called functional or movement fittings. These fittings are usually made of metallic materials such as steel.

Functional furniture is provided with at least one electromotive furniture drive. Such an electromotive furniture drive is mounted in the piece of furniture, which has fixed and movable furniture components. Fixed furniture components are e.g. frame components. Movable furniture components are e.g. fixed or resilient support surfaces of upholstery or a mattress of the seating and / or reclining furniture as well as manually or electrically adjustable sections or elements of the furniture.

The electromotive furniture drive is used to adjust the movable furniture components. The adjustment movement and drive force generated by the electromotive furniture drive are transmitted to the respective movable furniture component, with the electromotive furniture drive is supported on a fixed furniture component and the movable furniture component is adjusted relative to the fixed furniture component. The electromotive furniture drive can also be attached between two movable furniture components, and it can adjust them relative to one another.

Electromotive furniture drives are known from the prior art in a large number of different designs for different applications and purposes, e.g. as single drives, double drives and multiple drives.

Control devices are also known which are designed to control the respective electric motor of an adjustment drive on command or as a result of an event, e.g. a control command from a manual control, a limit switch, a detector, etc. The control devices have inputs and outputs. The outputs are electrically conductively connected, for example, to the respective electric motor. The inputs are, for example, connected to handheld remote controls or, possibly via evaluation circuits, to sensors and detectors in an electrically conductive manner. Other control devices have other outputs which exclusively convey an electrical or an electromechanical signal to a further control device which has the outputs described above for operating the respective electric motor.

In particular, the control devices described at the beginning have proven themselves. From the pamphlet DE 297 07 795 U1 a control device with an input is known, the input being electrically conductively connected to a metallic functional fitting, for example via a connecting line. The functional fitting or parts of the functional fitting, as a sensor, together with an evaluation circuit of the control device and the connecting line, form / form a detector. Via said connecting line, the evaluation circuit of the control device determines the level of the electrical capacitance of the functional fitting compared to a reference variable, for example the floor. Furthermore, the control device determines the change over time in the measured variable of the electrical capacitance detected by the evaluation circuit. Rapid changes in the electrical capacity of the functional fitting during operation of the motor indicate a malfunction, for example the occurrence of a pending or imminent entrapment of an object or a body part, provided that a person or an object moves into a danger area of the functional fitting or touches it. The respective electric motor is then switched off and, if necessary, reversed for a short period. In the JP2014064883A describes a furniture drive which is considered useful for understanding the invention.

The term "functional fitting" also includes metallic frames and parts, such as feet, of functional furniture. The term "sensor" here means an element of a functional fitting or a separate, electrically conductive element, such as a cable, rod antenna, flat iron, etc., which is attached to the furniture.

The control device mentioned at the beginning has proven itself very well. However, there is a disadvantage with large pieces of furniture, such as wide beds, or with complex pieces of furniture, such as when the functional fittings are divided into several groups.

Several groups can be formed if, for example in the case of a bed, an upper frame is connected to an underframe via electrically insulating rollers or glides. A further group can be formed if a foot flap fitting section of a functional fitting of an armchair with plastic bearings is arranged in an electrically insulated manner from the base frame. Other groups can be formed if the piece of furniture has a number of functional fittings which are each used for partial areas of the piece of furniture.

In order to create anti-trap protection for all movable furniture parts, according to the state of the art, all movable furniture parts or all sections of all functional fittings of the furniture must be electrically connected to one another via flexible lines. This method has also proven itself, however, the complexity of the control device is very high, which is reflected in the high quality and in the assembly effort of the electrical measuring circuit. Furthermore, it has been found that a complex adjustment of the system is necessary in order to prevent false tripping of the anti-trap protection.

The invention is based on the object of providing an electromotive furniture drive with a control device of the type mentioned at the outset, the disadvantages described no longer occurring or being significantly reduced, and which is also easy to assemble and easy to use.

The object is achieved by the arrangement as defined in claim 1, of more than one proximity and / or contact detector on functional furniture. A sensor or a group of sensors with an evaluation circuit forms such a detector, each sensor or group of sensors being connected to an input of the evaluation circuit. In an inventive way, the piece of furniture has a plurality of detectors which are individually connected in an electrically conductive manner to an input of the evaluation circuit of the control device.

The design of the various detectors makes it possible to safely monitor even a large functional fitting, for example in the case of the bed shown as functional furniture, without having to ensure that the furniture parts to be monitored are galvanically connected to one another or that there is sufficient capacitive coupling of the furniture parts is given among each other. The division of the total of the movable furniture parts to be monitored for anti-trap protection in functional furniture into at least two groups assigned to different detectors also prevents undesirable false responses due to interfering radiation, which can be coupled in more easily if the sensor surface is otherwise too large.

The control device has an evaluation circuit with a plurality of at least two inputs, each input being coupled to a sensor or a group of sensors. In addition, the evaluation circuit has a multiplexer, via which the at least two inputs can be connected sequentially to a detector circuit of the evaluation circuit. This measure of subdividing into several groups combined with a sequential evaluation with only one detector circuit enables the inexpensive manufacture and easy assembly of a highly sensitive anti-trap protection with high operational reliability at the same time.

In an advantageous embodiment of the electromotive furniture drive, the sensor or the group of sensors are conductively connected to one of the inputs of the at least one evaluation circuit. Alternatively, the sensor or the group of sensors are capacitively coupled to one of the inputs of the at least one evaluation circuit.

In a further advantageous embodiment of the electromotive furniture drive, the sensor is a sensor line and / or a conductive movable furniture part and / or a conductive element of a functional fitting.

Functional furniture according to the invention has at least two groups of movable furniture parts and at least one electromotive furniture drive according to one of the preceding claims. The advantages mentioned above in connection with the furniture drive result.

Fig. 1

eine schematische Perspektivansicht einer beispielhaften Möbelanordnung; und

Fig. 2

ein Blockschaltbild der von Komponenten der Möbelanordnung.

The invention is explained in more detail below using an exemplary embodiment with the aid of figures. Show it:

Fig. 1

a schematic perspective view of an exemplary furniture arrangement; and

Fig. 2

a block diagram of the components of the furniture arrangement.

Fig. 1 shows an example of a furniture arrangement with a functional piece of furniture 1. As a functional piece of furniture 1, a bed is shown here as an example. The functional piece of furniture 1 has a basic element 2, here a frame-like frame with feet. A slatted frame with a functional fitting 3 is inserted into the base element 2. The slatted frame carries a mattress M.

In the example shown, functional furniture 1 has two movable furniture parts 5 and 6, which are movable relative to a fixed base part 4 arranged between them. Specifically, the two movable furniture parts 5, 6 are a back part and a leg part. For the sake of simplicity, they are also referred to below as the back part 5 and leg part 6.

The movable arrangement of the movable furniture parts 5 and 6 is realized by the functional fitting 3, also called movement fitting. The movement is designed to be displaceable and / or pivotable.

The movably mounted back part 5 and the leg part 6 are each coupled to an electromotive adjustment drive 7, 8. The back part 5 is coupled to the electromotive adjustment drive 7. The electromotive adjustment drive 8 is provided for moving or adjusting the leg part 6.

The electromotive adjustment drives 7, 8 are designed here as linear drives. The linear drives have one or a number of electric motors, each motor being followed by a speed reducing gear with at least one gear stage. The speed reducing gear can be followed by a further gear, for example in the form of a threaded spindle gear, which generates a linear movement of the output member from the rotary movement of the motor. The last transmission link or a further link connected to it forms an output link. The output member of the respective electromotive adjustment drive is connected to the respective furniture component (back part 5, leg part 6) or, alternatively, to a component connected to the base frame 2, so that when the electric motor of the respective adjustment drive 7, 8 is operated, the movable furniture components are adjusted relative to one another become.

The electromotive adjustment drives 7, 8 are connected to a control device 9. This connection can be designed, for example, as a pluggable cable connection, which is not shown in detail here. The control device 9 has an electrical supply unit which provides the electrical energy, for example from the network, for the electromotive adjustment drives 7, 8. For this purpose, the control device 9 in this example can be connected to a mains connection via a mains cable (not shown) with a mains plug. The mains plug conducts the mains voltage on the input side to the electrical supply unit via the mains cable the control device 9, which on the secondary side emits a low voltage in the form of a direct voltage and forwards this to an engine control.

As an alternative to this, the control device 9 is preceded by a network-dependent voltage supply, likewise not shown, with a network input and a secondary-side low-voltage output, which supplies the low-voltage in the form of a direct voltage via a line.

The piece of furniture 1 is also assigned an operating unit 20, with the operating elements 21 of which the electromechanical adjustment drives 7, 8 can be controlled via the control device 9. When an operating element 21 is actuated, a control signal for activating the respective electromechanical adjusting drive 7, 8 is transmitted to the control device 9 wirelessly or by wire via a transmission path.

The control device 9 has switching elements which convert the control signals of the transmission path into switching signals for switching the respective adjusting drive 7, 8. The switching elements can be, for example, relay switches and / or semiconductor switches. The manually operable operating elements 21 of the operating unit 20 generate control signals which are converted by the receiver of the control device 9 into control currents for the switching elements. In the case of a wired operating unit 20, the operating elements 21 switch the control current of the relay switches or the semiconductor switches. In both cases, the circuit breakers of the relay switches or the semiconductor switches switch the high motor current of the respective electromotive adjustment drive 7, 8.

In order to prevent a body part from being trapped when moving the movable furniture parts 5, 6, the functional furniture 1 shown is equipped according to the application with proximity and / or contact detectors that prevent the adjustment devices 7, 8 from being actuated via the control device 9 when approaching one Sensor or a touch of the sensor is detected. This is discussed below in connection with Fig. 2 explained in more detail.

Fig. 2 shows the system of Fig. 1 in a schematic block diagram. In this figure, the same reference symbols denote elements that are the same or have the same effect as in FIG Fig. 1 .

As related to Fig. 1 is described, the furniture fitting has the two movable furniture parts, the back part 5 and the leg part 6, which are movable with respect to a fixed base part 4. The movement is achieved via the two electromotive adjustment drives 7, 8 which act on the back part 5 and the leg part 6. The mechanical coupling of the adjustment drives 7, 8 to the back or leg part 5, 6 is with the Fig. 2 symbolized only by a dashed line. The adjustment drives 7, 8 are controlled by the control device 9 and supplied with power. A power supply for the control device 9, for example via an integrated or external power supply unit, is in the Fig. 2 not shown.

In order to prevent a body part from being trapped when moving one of the movable furniture parts 5, 6, for example between the movable furniture part 5, 6 and a stationary part of the functional furniture 1, an evaluation circuit 10 is provided that allows one of the movable furniture parts 5, 6 to come into contact detected. In the example shown, the evaluation circuit 10 is arranged externally from the control device 9 and is electrically connected to it via an output 13 of the evaluation circuit 10. In alternative configurations, the evaluation circuit 10 can be integrated into the housing of the control device 9.

In the example shown, the evaluation circuit 10 has two inputs 11, 12 which are coupled to the furniture parts 5, 6 via sensor lines 111, 121. Correspondingly, two sensor groups are formed, each comprising the sensor line 111 or 121 and the furniture part 5, 6. Together with the evaluation circuit 10, two independent contact and / or proximity detectors are formed as anti-trap protection.

Touching or approaching the furniture parts 5, 6 is detected by the evaluation circuit 10 via the sensor lines 111, 121. A signal is generated at an output 13 of the evaluation circuit 10, which signal causes the control device 9 to stop at least one of the two adjusting drives 7, 8. There It can be provided that a touch of the furniture part 5 or approach to the furniture part 5 detected via the sensor line 111 only stops the associated adjustment drive 7, whereas the detection of a touch of the furniture part 6 or approach to the furniture part 6 through the sensor line 121 stops the associated adjustment drive Adjustment drive 8 stops. However, each contact preferably leads to a stopping of all adjustment drives 7, 8, which may be actuated simultaneously, regardless of which sensor line 111, 121 or which of the inputs 11, 12 is detected by the evaluation circuit 10.

In a further development, it can also be provided that the adjustment drives 7, 8 are not only stopped, but that a moving adjustment drive 7, 8 is operated in the opposite direction of movement for a predetermined short period of time after stopping in order to release a body part that may already have been trapped .

The detection of contact with the sensors by the evaluation circuit 10 is preferably carried out capacitively. This capacitive contact or proximity detection can be set so sensitively that no direct galvanic contact with an input 11 or an exposed section of the sensor line 111, 121 is required, but rather a contact or approach to isolated sections of the sensor line 111 or the one with it coupled furniture parts 5, 6 or likewise coupled therewith sections of a functional fitting can be detected. In this way, it is also possible to detect contact with a lacquered or plastic-coated area of the movable furniture parts 5, 6.

If moving elements to be monitored, for example the furniture parts 5, 6 or other sections of functional fittings, are made entirely of an insulating material, for example wood or plastic, a conductive element can be applied. The conductive element can consist in the continuation of the sensor line 111, 121 itself. Alternatively, for example, metallized foils can be glued onto the non-conductive material. It is also possible to make an insulating material with a conductive coating, for example based on a conductive polymer, on the surface conductive. Substances or Yarns with woven-in metallic threads or fibers are used as conductive elements.

In the Fig. 2 two different types of coupling of the sensor lines 111, 121 to the movable furniture parts 5, 6 are shown by way of example. The sensor line 111 contacts the furniture part 5 directly in a conductive connection 112. If the furniture part 5 is a lacquered steel tube, the lacquer can be removed from the surface at one point and the sensor line 111 attached at this point. Alternatively, for example, a self-tapping screw can be screwed into the metal tube of the furniture part 5, via which the conductive connection 112 is established.

In contrast, the sensor line 121 is coupled to the furniture part 6 via a capacitive coupling 122. For this purpose, the sensor line 121 has a flat electrode at its end, which is glued to a painted area of the furniture part 6, for example by means of a self-adhesive layer. The change in capacitance of the furniture part 6 caused by a body part approaching or touching it is transmitted by this capacitive coupling 122 to the sensor line 121 and thus to the evaluation circuit 10.

In the illustrated embodiment of the Fig. 2 For example, two inputs 11, 12 and two corresponding sensor lines 111, 121 are provided. It goes without saying that this number is purely exemplary. It is also possible to provide more than the two sensor lines 111, 121 shown, by means of which more than two groups of monitored movable furniture parts 5, 6 are defined on the functional furniture 1.

The design of the various detectors also makes it possible to safely monitor a large functional fitting, for example in the case of the bed shown as functional furniture 1, without having to ensure that furniture parts 5, 6 to be monitored are galvanically connected to one another or that sufficient capacitive coupling of the furniture parts is given. The division of the total of movable furniture parts 5, 6 to be monitored in functional furniture for anti-trap protection into at least two Groups that are assigned to different detectors also prevent undesired erroneous response due to interfering radiation, which can be coupled in more easily if the sensor surface is otherwise too large.

The evaluation circuit 10 can internally have a single detector circuit for the change in capacitance, which is connected in a multiplex process to the at least two inputs 11, 12 in rapid alternation (sequential evaluation). This measure of subdividing into several groups and the sequential evaluation with only one detector circuit enables the inexpensive manufacture and easy assembly of a highly sensitive anti-trap protection with high operational reliability at the same time.

Alternatively, the evaluation circuit 10 can have a number of detector circuits corresponding to the number of inputs 11 for a change in capacitance, which are coupled to one another on the output side via a corresponding logic circuit, for example an "or" link, so that when each of the detector circuits responds, a corresponding output signal at the output 13 is issued. In order to be able to use the evaluation circuit 10 universally for a plurality of functional fittings or furniture, a larger number of inputs 11, 12 can be provided, for example four inputs 11, 12, which also offers a sufficient number of groups for larger functional fittings.

When such an evaluation circuit is used in furniture that only requires two or three monitored groups, unused inputs 11, 12 can be set inactive, for example by being connected to a ground potential. Alternatively, individual inputs 11, 12 can be selectively set inactive by parameterizing a multiplexer used on the input side or a logic used on the output side in the evaluation circuit 10.

The detector circuits for detecting a change in capacitance are preferably self-adjusting, so that a slow change in capacitance, which is caused, for example, by changing environmental conditions such as changing humidity, does not lead to false triggering. The sensor lines 111, 121 are prefers ordinary single-core cables without shielding, which are inexpensive and easy to lay.

If several control devices are provided on a functional piece of furniture, an evaluation circuit can be assigned to each control device.

Reference number

1

Functional furniture

2

Basic element

3

Functional fitting

4th

fixed base

5

movable furniture part (back part)

6th

movable furniture part (leg part)

7, 8

Adjustment drive

9

Control device

10

Evaluation circuit

11, 12

entrance

111, 121

Sensor cable

112

conductive connection

122

capacitive coupling

13th

Exit

20th

Control unit

21

Control element

M.

mattress

Claims (8)

1. Electromotive furniture drive for adjusting movable furniture parts (5, 6) of an item of functional furniture (1), having a control unit (9), at least one adjustment drive (7, 8) with an electric motor, and at least one analysis circuit (10) with an input (11, 12) which is connectable in an electrically conductive manner together with a sensor attached to the item of functional furniture (1) and forms a proximity and/or touch detector, wherein
   at least two proximity and/or touch detectors are each formed by a sensor or a group of sensors with the at least one analysis circuit (10), which can be associated with different movable furniture parts (5, 6) of the item of functional furniture (1), wherein
   an analysis circuit (10) that has at least two inputs (11, 12) is present, wherein each of the inputs (11, 12) is coupled to a sensor or a group of sensors, characterized in that
   the analysis circuit (10) has a multiplexer, via which the at least two inputs (11, 12) are sequentially connectable to a detector circuit of the analysis circuit (10).
2. The electromotive furniture drive according to Claim 1, wherein multiple control units (9) are provided, wherein each control unit (9) is associated with an analysis circuit (10) and each of the analysis circuits (10) is coupled to at least one sensor or one group of sensors.
3. The electromotive furniture drive according to Claim 1 or 2, wherein the sensor or the group of sensors is/are conductively connected to one of the inputs (11, 12) of the at least one analysis circuit (10).
4. The electromotive furniture drive according to any one of Claims 1 to 3, wherein the sensor or the group of sensors is/are capacitively coupled to one of the inputs (11, 12) of the at least one analysis circuit (10).
5. The electromotive furniture drive according to any one of Claims 1 to 4, wherein the sensor is a sensor line (111, 121) and/or a conductive movable furniture part (5, 6) and/or a conductive element of a functional fitting.
6. An item of functional furniture (1) having at least two groups of movable furniture parts (5, 6), comprising at least one electromotive furniture drive according to any one of the preceding claims.
7. The item of functional furniture according to Claim 6, wherein each of the at least two groups of movable furniture parts (5, 6) represents a sensor and forms a proximity and/or touch detector in each case together with at least one analysis circuit (10).
8. The item of functional furniture according to Claim 7, wherein each of the at least two groups of movable furniture parts (5, 6) is associated with a functional fitting of the item of functional furniture.

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