Furniture drive

Abstract

The invention relates to a furniture drive (1) for adjusting an arm (2), comprising a coupling device (3) for adjusting the arm (2), which coupling device has at least one drive part (4) and at least one drive output part (5) that can be rotated relative to the drive part, the coupling strength between the at least one drive part (4) and the at least one drive output part (5) can be adjusted by means of an adjusting device, the at least one drive part (4) and the at least one drive output part (5) being arranged at a distance from one another in order to form a gap (6), the gap (6) being filled with a magnetorheological medium (7) which can be influenced by a magnetic field, the adjustment device for adjusting the coupling strength has a device (8) for generating a magnetic field for the magnetic polarization of the magnetorheological medium (7).

Description

Technical Field

[0001] The invention relates to a furniture drive having the features of the preamble of claim 1 and to a piece of furniture having such a furniture drive. Background Art

[0002] Furniture drives for adjusting arms are known in the prior art which have different coupling devices for the adjusting arms.

[0003] EP 1 861 572 B1 shows a piece of furniture with a furniture drive and a movable adjusting arm, wherein a coupling device acts between the electric drive and the adjusting arm, which coupling device has an overrunning clutch in at least one direction of rotation over a defined rotation angle range for free movement of the adjusting arm into an open position and / or a closed position. Disadvantageously, with a coupling device of this type, the coupling strength cannot be adjusted.

[0004] EP 1 903 909 B1 shows a coupling of a furniture drive that can be switched by means of a cable drive. The coupling strength cannot be adjusted for this type of coupling device. In addition, wear phenomena can occur disadvantageously in such friction-based couplings.

[0005] EP 1 981 371 B1 shows a furniture drive having a drive unit and a sliding coupling, wherein the sliding coupling is designed such that it decouples the drive unit and the propeller from one another when a predetermined torque is exceeded. The sliding coupling operates based on the diameter of the wrap spring, which disadvantageously means that the coupling strength for a coupling device of this type can only be adjusted with difficulty, for example by completely replacing the wrap spring.

[0006] EP 2 086 372 B1 shows a furniture drive having a coupling device for at least temporarily transmitting force to an adjusting arm, wherein the coupling device is designed in the form of a sleeve freewheel. Disadvantageously, the coupling strength cannot be adjusted for a coupling device of this type. Summary of the invention

[0007] The object of the present invention is to provide a furniture drive and a piece of furniture which avoid the above-mentioned problems.

[0008] This object is achieved by a furniture drive and a piece of furniture having such a furniture drive having the features of claim 1. Advantageous embodiments of the invention are defined in the dependent claims.

[0009] The furniture drive is suitable for driving the adjusting arm. The furniture drive can be connectable to the adjusting arm or have an adjusting arm. At least one movable furniture part of the furniture can be connectable to the adjusting arm of the furniture drive or is connected to the adjusting arm of the furniture drive. The furniture can have a furniture carcass, wherein the furniture part can be arranged in an opening of the furniture carcass or wherein the furniture part can close an opening of the furniture carcass. The movement of the adjusting arm can be performed between a retracted position and a retracted position of the furniture part or between an open position and a closed position of the furniture part.

[0010] The furniture drive has a coupling device, which has at least one drive component and at least one drive output component that is rotatable relative to the drive component. The drive of the furniture drive can act on the drive component. The drive output component can be connectable to the adjustment arm or connected to the adjustment arm. The furniture drive can have a plurality of coupling devices. The coupling device can also have, for example, a plurality of drive components and a plurality of drive output components that are connected in series.

[0011] It is proposed that the coupling strength between at least one drive component and at least one drive output component can be adjusted using an adjustment device. The coupling strength can be adjusted between two situations: a substantially rigid coupling between at least one drive component and at least one drive output component and a substantially non-force-transmitting connection between at least one drive component and at least one drive output component.

[0012] In order to implement the coupling device, it is proposed that at least one drive component and at least one drive output component are arranged spaced apart from each other to form a gap. For example, at least one drive component and at least one drive output component can be arranged side by side along a common axis at a predetermined or predeterminable spacing, and the gap is formed by the spaced arrangement.

[0013] In this case, it is provided that the gap is filled with a magnetorheological medium which can be influenced by a magnetic field.

[0014] The adjusting device is designed to adjust the coupling strength, wherein for this purpose the adjusting device has a device for generating a magnetic field for magnetic polarization of the magnetorheological medium.

[0015] Magnetorheological media can consist of magnetizable solid particles in a carrier fluid. When an external magnetic field is applied, the solid particles can be magnetized and form chains along the field lines of the magnetic field. Thus, the magnetorheological medium can be transformed from a fluid state to a substantially solid state in a controlled manner. As a result, the coupling strength can be adjusted without wear simply by adjusting the device for generating the magnetic field.

[0016] Advantageously, the furniture drive can be coupled to and decoupled from the actuating arm by means of the coupling device with a coupling strength corresponding to the polarization of the magnetorheological medium.

[0017] The coupling device can be used, for example, as an overload clutch, a freewheeling clutch, for coupling a damping device or for coupling a drive.

[0018] The device for generating a magnetic field for polarizing a magnetorheological medium can have at least one electromagnet with a coil that can be energized. By adjusting the current flowing through the coil, the coupling strength can be adjusted depending on the polarization of the magnetorheological medium. Preferably, the energizable coil is arranged statically in the furniture drive. At least one drive component and at least one drive output component can each be arranged in the furniture drive in a rotatable manner relative to the coil.

[0019] It should not be excluded that the device for generating a magnetic field for polarizing a magnetorheological medium has a plurality of electromagnets and / or at least one permanent magnet.

[0020] If the drive element and the drive output element are arranged on an axis which extends through the coil of the device for generating a magnetic field, the magnetic field and thus the magnetorheological medium can be polarized along this axis.

[0021] The drive element can be made of a magnetizable material and at least partially extend into the inner region of the coil. The magnetic flux generated by the energized coil can be guided by the drive element into the region of the gap. Preferably, a drive shaft extending axially from the drive element can extend into the inner region of the coil, the drive shaft being used for coupling to a drive of the furniture drive.

[0022] In order to guide the drive output component, the drive component can have a support shaft that protrudes axially from the drive component in the center. The drive output component can be rotatably supported on the drive component, for example, by means of a ball bearing arranged on the support shaft that protrudes axially from the drive component in the center. Preferably, the support shaft is made of a magnetizable material for conducting magnetic flux.

[0023] The drive element and the drive output element can be arranged adjacent to one another along a common axis of rotation, wherein the gap can be designed at least axially.

[0024] The drive component can be configured at least in sections to be disk-shaped. Here, the disk-shaped section of the drive component can be arranged to face the gap. In other words, the disk-shaped section of the drive component can form a boundary surface of the gap.

[0025] The drive component can have an axial projection at least in sections in order to form an open U-shaped profile cross section. The drive component can in particular be configured at least in sections as a disk and at least in sections have an axial projection extending therefrom, for example a circumferentially axially protruding web. Preferably, the axial projection or web can be arranged in a radial edge region of the drive component. The axial projection or web can form a boundary surface of the gap.

[0026] The drive output component can be configured at least in sections to be disk-shaped. Here, the disk-shaped section of the drive output component can be arranged to face the gap. In other words, the disk-shaped section of the drive output component can form a boundary surface of the gap.

[0027] In an advantageous embodiment, the drive component can have an axial projection at least in sections in order to construct an open U-shaped profile cross section, and the drive output component is at least partially arranged in the U-shaped profile cross section of the drive component. Here, the gap can be substantially limited by the drive component and the drive output component.

[0028] The drive member may at least partially radially surround the drive output member.

[0029] The gap can be formed at least in the radial direction by the arrangement of the drive element relative to the drive output element.

[0030] Advantageously, a seal for sealing the magnetorheological medium is arranged radially between the drive component and the drive output component. When the drive component and the drive output component are arranged on an axis extending through the coil of the device for generating a magnetic field, the magnetic field and thus the polarization of the magnetorheological medium can be carried out axially. By radially arranging the seal, the effective area of ​​the gap can be maximized.

[0031] In order to form a positive connection with the magnetorheological medium, the drive component and / or the drive output component can have a structured surface facing the gap at least in sections. The structured surfaces can in particular have an axial offset with respect to each other. The structured surfaces can be implemented in the drive component and / or the drive output component in the form of radial webs and radial recesses. Through the structured surfaces, shear forces can act on the magnetorheological medium when the drive output component rotates relative to the drive component.

[0032] The furniture drive can have an electric motor for driving the adjusting arm, wherein the adjusting arm can be coupled and decoupled from the electric motor by means of a coupling device in a manner corresponding to the coupling strength.

[0033] In order to be connected to the drive of the furniture drive, the drive element can have a drive shaft extending axially from the drive element in the center. The drive element can be rotatably supported in the furniture drive, for example, by a ball bearing arranged on the drive shaft extending axially from the drive element in the center.

[0034] If the furniture drive has an electric motor for driving the adjusting arm, and the adjusting arm can be coupled to and decoupled from the electric motor by means of a coupling device corresponding to the coupling strength, then when the adjusting arm connected to the drive output element moves, the electric motor can be operated as a generator in order to dampen this movement. In particular, damping of the movement of the adjusting arm can be desirable in the end region of the adjusting arm where the movement is limited.

[0035] The furniture drive advantageously has a control device for adjusting the device. If the adjustment device for adjusting the coupling strength has a device for generating a magnetic field, the device having at least one electromagnet with a coil that can be energized, the control device can control and / or adjust the current intensity of the current flowing through the coil. This control and / or adjustment can be carried out, for example, based on the adjustment angle of the adjustment arm connected to the drive output component. For this purpose, for example, an angle sensor can be used to detect the rotation angle of the drive output component relative to the housing of the furniture drive, and the rotation angle can be transmitted to the control device. The motor of the furniture drive can also be controllable by the control device.

[0036] The furniture drive can have a mechanical force accumulator which is connected or can be connected to an adjusting arm which is connected to a drive output element. By means of a coupling device, forces from the force accumulator and / or forces caused by the electric motor can be applied to the adjusting arm. Thus, for example, the mechanical force accumulator can be used to compensate for the weight of a furniture part connected to the adjusting arm and the electric motor can be used to drive or dampen the movement of the furniture part.

[0037] A piece of furniture having at least one furniture drive as described above is also claimed, wherein at least one movable furniture part of the furniture can be connected or coupled to an adjustment arm of the furniture drive, which is connected to a drive output element.

[0038] The piece of furniture can have a furniture carcass with at least one wall, wherein the furniture drive can be arranged substantially completely in a recess in the wall of the furniture carcass in the installed position or can be arranged substantially completely in a recess in the wall of the furniture carcass. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Embodiments of the present invention are discussed based on the accompanying drawings. The accompanying drawings show:

[0040] Figure 1a and Figure 1bA perspective view and a sectional view of a first embodiment of a furniture drive are shown,

[0041] Figure 2 shows an exploded view of an embodiment of a coupling device,

[0042] Figure 3a and Figure 3b shows a perspective view and a cross-sectional view of an embodiment of a coupling device,

[0043] Figure 4a and Figure 4b showing a cross-sectional view of a coupling device and parts of a coupling device,

[0044] Figure 5a and Figure 5b showing a cross-sectional view of components of a coupling device,

[0045] Figure 6 A sectional view showing a second embodiment of a furniture drive device,

[0046] Figure 7a and Figure 7b A perspective view of the furniture is shown, and

[0047] Figure 8 A schematic diagram of a furniture drive with a control device is shown. Specific embodiments

[0048] Figure 1a A perspective view of a first embodiment of a furniture drive 1 is shown. Figure 6 1 shows a sectional view of a second embodiment of a furniture drive 1 in a side view, wherein the adjusting arm 2 connected to the furniture drive is shown in this view. Figure 1a The first exemplary embodiment of the furniture drive 1 shown in FIG. 1 can also be provided with an adjusting arm 2 .

[0049] exist Figure 1a 2 shows a furniture drive 1 for an adjusting arm 2 , which comprises a housing 25 and a coupling device 3 having a receiving area 26 for the adjusting arm 2 .

[0050] As in Figure 1b As can be seen from the sectional view of FIG. 1 , the furniture drive 1 comprises at least one drive element 4 and at least one drive output element 5 which is rotatable relative to the drive element.

[0051] The at least one drive element 4 and the at least one drive output element 5 are arranged at a distance from one another in order to form an axial and radial gap 6. The gap 6 is filled with a magnetorheological medium 7, which is indicated by hatching.

[0052] The coupling strength between at least one drive element 4 and at least one drive output element 5 can be adjusted by means of the adjusting device having the device 8 for generating a magnetic field, wherein the coupling strength can be adjusted by means of the magnetic polarization of the magnetorheological medium 7 .

[0053] The actuating arm 2 can be coupled to the furniture drive 1 by means of the coupling device 3 with a coupling strength corresponding to the polarization of the magnetorheological medium 7 and can be decoupled.

[0054] In the exemplary embodiment shown, the device 8 for generating a magnetic field polarizing the magnetorheological medium 7 has at least one electromagnet with an energizable coil 9. As shown, the energizable coil 9 is arranged statically in the furniture drive 1.

[0055] exist Figure 2 An exploded view of an embodiment of a coupling device 3 is shown in FIG. Figure 3a and Figure 3b A perspective view and a sectional view of the coupling device 3 are shown. Figure 4a and Figure 4b as well as Figure 5a and Figure 5b Cross-sectional views of coupling devices and components of coupling devices are shown.

[0056] As can be seen in the figure, the drive part 4 has a drive shaft 10 extending axially from the drive part 4 and is used to couple to a drive of the furniture drive 1, which, as shown, extends into the inner region of the coil 9. The drive part 4 can be rotatably supported in the housing 25 of the furniture drive 1 via the axially extending drive shaft 10, for example via a ball bearing.

[0057] In the exemplary embodiment shown, the drive element 4 is at least partially disk-shaped and has an open U-shaped profile cross section (see in particular Figure 2 and Figure 4b ) and has a circumferential axial projection 12 in the edge region.

[0058] Furthermore, the drive element 4 has a bearing shaft 12 for guiding the drive output element 5, which protrudes axially from the drive element 4 in the center. The drive output element 5 can be rotatably supported on this bearing shaft, for example, by means of a ball bearing.

[0059] In the embodiment shown, the drive output element 5 is at least partially disk-shaped.

[0060] As especially in Figure 1b and Figure 4b As can be seen in , the drive element 4 and the drive output element 5 can be arranged adjacent to one another along a common rotation axis, and the gap 6 can be formed at least axially. The gap 6 can also be formed at least radially.

[0061] Due to the open U-shaped profile cross section of the drive element, the drive output element 5 can be arranged at least partially in the U-shaped profile cross section of the drive element 4. In this case, the drive element 4 can at least partially surround the drive output element 5 in radial direction.

[0062] Radial seals 13, 14 can be arranged between the drive element 4 and the drive output element 5, so that the volume for the magnetorheological medium 7 formed between the drive element 4 and the drive output element 5 is sealed. Figure 2 is shown in the exploded view.

[0063] In order to fill the volume for the magnetorheological medium 7 formed between the drive element 4 and the drive output element 5 , ventilation openings 15 can be provided in the drive output element.

[0064] exist Figure 2 It can be seen that, in order to form a positive connection with the magnetorheological medium 7 , the drive element 4 and the drive output element 5 can at least partially have a structured surface facing the gap 6 with webs 16 and recesses 17 .

[0065] exist Figure 6 A second embodiment of a furniture drive 1 is shown in FIG. The furniture drive can have a coupling device 3 as described above. In this embodiment, the coupling device 3 is connected to a movable furniture part 21 (see FIG. 2 ) by means of a connecting rod 28. Figure 7a and Figure 7b ) is connected to the adjusting arm 2. The connecting rod 28 can be connected to the covered connection area 26 in the figure, for example, by a gear and a rack.

[0066] The actuating arm 2 can be coupled to the furniture drive 1 by means of the coupling device 3 with a coupling strength corresponding to the polarization of the magnetorheological medium 7 and can be decoupled.

[0067] In the second exemplary embodiment shown, the furniture drive 1 has an electric motor 18 for driving an actuating arm 2 connected to a drive output element 5. The actuating arm 2 can be coupled to the electric motor 18 by means of a coupling device 3 with a corresponding coupling strength and can be decoupled.

[0068] In the second exemplary embodiment, the furniture drive 1 also has a mechanical force accumulator 19, which is connected via a rod to the actuating arm 2. The coupling device 3 can be used to apply the force from the force accumulator 19 and / or the force caused by the electric motor 18 to the actuating arm 2 connected to the drive output element 5, depending on the coupling strength.

[0069] Furthermore, during the movement of the actuating arm 2 , in particular in the end region of the actuating arm 2 where the movement is limited, the electric motor 18 can be operated as a generator in order to dampen the movement.

[0070] exist Figure 7a and Figure 7b 2 shows an exemplary embodiment of a piece of furniture 20 which has two furniture drives 1 as described above. A movable furniture part 21 of the piece of furniture 20 in the form of a furniture flap is connected to an adjusting arm 2 of the furniture drive 1 .

[0071] As shown, the furniture 20 has a furniture body 22 having at least one wall 23, wherein Figure 7b In the illustrated installation position, a respective furniture drive device 1 can be arranged substantially completely in a recess 24 in a wall 23 of a furniture carcass 22 .

[0072] Figure 8 A furniture drive 1 is schematically shown, which has a control device 29 for a device 8 for generating a magnetic field for adjusting the device. If the adjusting device for adjusting the coupling strength has a device 8 for generating a magnetic field, the device has at least one electromagnet with a coil 9 that can be energized as described above (see, for example, Figure 1b ), the control device 29 can control and / or adjust the current intensity of the current flowing through the coil 9. The control and / or adjustment can be performed, for example, based on the adjustment angle of the adjustment arm 2 connected to the drive output component. For this purpose, for example, an angle sensor 30 can be used to detect the rotation angle of the drive output component 5 relative to the housing 25 of the furniture drive device 1 (see, for example Figure 1a or Figure 6 ), and transmits the rotation angle to the control device 29. The motor 18 of the furniture drive can also be controlled by the control device 29.

[0073] The control device 29 can be integrated in the furniture drive 1 or be designed separately from the furniture drive.

[0074] Reference numerals list

[0075] 1 Furniture drive

[0076] 2 Adjustment arm

[0077] 3 Coupling equipment

[0078] 4 Drive components

[0079] 5 Drive output components

[0080] 6 Clearance

[0081] 7 Magnetorheological media

[0082] 8 Equipment for generating magnetic fields

[0083] 9 Coil

[0084] 10 Drive shaft

[0085] 11 Support shaft

[0086] 12 Protrusion

[0087] 13 Seals

[0088] 14 Seals

[0089] 15 Ventilation openings

[0090] 16 Connector

[0091] 17 recess

[0092] 18 Motor

[0093] 19 Mechanical accumulator

[0094] 20 Furniture

[0095] 21 Furniture parts

[0096] 22 specific

[0097] 23 wall

[0098] 24 recess

[0099] 25 Shell

[0100] 26 Connection Area

[0101] 27 Transmission

[0102] 28 Connecting rod

[0103] 29 Control Device

[0104] 30 Sensors

Claims

1. A furniture drive (1) for an adjusting arm (2), the furniture drive comprising a coupling device (3) for the adjusting arm (2), the coupling device comprising at least one drive component (4) and at least one drive output component (5) rotatable relative to the drive component, characterized in that: The coupling strength between the at least one drive component (4) and the at least one drive output component (5) can be adjusted by means of an adjustment device, wherein the at least one drive component (4) and the at least one drive output component (5) are arranged at a distance from each other in order to form a gap (6), wherein the gap (6) is filled with a magnetorheological medium (7) that can be influenced by a magnetic field, and the adjustment device for adjusting the coupling strength has a device (8) for generating a magnetic field, which is used for magnetic polarization of the magnetorheological medium (7).

2. The furniture drive device according to claim 1, wherein: The adjusting arm (2) connected to the drive output element (5) can be coupled to and decoupled from the furniture drive (1) by means of the coupling device (3) with a coupling strength corresponding to the polarization of the magnetorheological medium (7).

3. The furniture drive device according to claim 2, wherein: The device (8) for generating a magnetic field has at least one electromagnet with a coil (9) to which current can be supplied, the magnetic field being used for magnetic polarization of the magnetorheological medium (7), wherein the coil (9) to which current can be supplied is preferably arranged statically in the furniture drive (1).

4. The furniture drive device according to claim 3, wherein: The drive component (4) is made of a magnetizable material and at least partially extends into the inner region of the coil (9), wherein preferably, a drive shaft (10) extending axially from the drive component (4) extends into the inner region of the coil.

5. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) has a bearing shaft (12) for guiding the drive output element (5) which protrudes axially from the drive element (4) in a central manner, wherein the bearing shaft (12) is preferably made of a magnetizable material.

6. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) and the drive output element (5) are arranged adjacent to one another along a common rotation axis, and the gap (6) is formed at least axially.

7. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) is designed at least in sections in the form of a disk.

8. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) has an axial projection (12) at least in sections, preferably in the edge region, in order to form an open U-shaped profile cross section.

9. The furniture drive device according to any one of the preceding claims, wherein: The drive output component (5) is designed at least in sections in a disk-like manner.

10. The furniture drive device according to any one of the preceding claims, wherein: The drive component (4) has an axial projection (12) at least in sections in order to form an open U-shaped profile cross section, and the drive output component (5) is at least partially arranged in the U-shaped profile cross section of the drive component (4).

11. The furniture drive device according to claim 10, wherein: The drive component (4) at least partially surrounds the drive output component (5) in the radial direction.

12. The furniture drive device according to any one of the preceding claims, wherein: The gap (6) is designed at least radially.

13. The furniture drive device according to claim 12, wherein: At least one radial seal (13, 14) is arranged between the drive component (4) and the drive output component (5).

14. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) and / or the drive output element (5) has, at least in sections, a structured surface facing the gap (6) for forming a positive connection with the magnetorheological medium (7).

15. The furniture drive device according to any one of the preceding claims, wherein: The furniture drive (1) has a motor (18) for driving an adjustment arm (2) connected to the drive output component (5), and the adjustment arm (2) can be coupled to and decoupled from the motor (18) in a manner corresponding to the coupling strength using the coupling device (3).

16. The furniture drive device according to claim 15, wherein: The furniture drive (1) comprises a mechanical force accumulator (19) which can be connected to an adjusting arm (2) or the force accumulator is connected to an adjusting arm (2), and the adjusting arm is connected to the drive output component (5), wherein the coupling device (3) can be used to apply a force from the force accumulator (19) and / or a force caused by the electric motor (18) to the adjusting arm (2) connected to the drive output component (5) in a manner corresponding to the coupling strength.

17. The furniture drive device according to any one of the preceding claims, wherein: The drive element (4) has a drive shaft (10) which projects axially from the drive element (4) in a central position for connection to a drive of the furniture drive device (1).

18. The furniture drive device according to any one of the preceding claims, wherein: The furniture drive has a motor (18) for driving an adjusting arm (2), and the adjusting arm (2) can be coupled to and decoupled from the motor (18) by means of the coupling device (3) in a manner corresponding to the coupling strength, wherein during movement of the adjusting arm (2), in particular in the end region of the adjusting arm (2) where movement is limited, the motor (18) can be operated as a generator to dampen the movement.

19. A piece of furniture (20) having at least one furniture drive (1) according to any one of the preceding claims, wherein: At least one movable furniture part (21) of the piece of furniture (20) is connectable to an adjustment arm (2) of the furniture drive (1) or is connected to the adjustment arm.

20. The piece of furniture (20) according to claim 19, wherein The piece of furniture (20) comprises a furniture carcass (22) having at least one wall (23), wherein the furniture drive (1) in the installed position can be arranged substantially completely in a recess (24) in the wall (23) of the furniture carcass (22) or substantially completely in the recess.

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