Furniture drive

Abstract

The invention relates to a furniture drive (1) for an actuating arm (2), the drive having a coupling device (3) for coupling an actuating arm (2) to at least one drive part (4) and at least one output part (5) rotatable relative thereto, wherein a coupling intensity between the at least one drive part (4) and the at least one output part (5) is adjustable by means of an adjustment device, wherein the at least one drive part (4) and the at least one output part (5) are arranged at a distance from one another 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 intensity has a device for generating a magnetic field (8) for magnetic polarisation of the magnetorheological medium (7).

Description

[0001] Furniture drive

[0002] The invention relates to a furniture drive with the features of the preamble of claim 1 and to a piece of furniture with such a furniture drive.

[0003] In the state of the art, furniture drives for an actuating arm with different coupling devices for the actuating arm are known.

[0004] EP 1 861 572 B1 shows a piece of furniture with a furniture drive and a movable actuating arm. A coupling device is operative between an electric drive and the actuating arm. The coupling device has a freewheel for freely moving the actuating arm into an open position and / or into a closed position in at least one direction of rotation over a limited angle of rotation. The disadvantage of this type of coupling device is that it cannot be adjusted in terms of coupling intensity.

[0005] EP 1 903 909 B1 shows a clutch for a furniture drive that can be switched by means of a cable pull. The clutch intensity is not adjustable for this type of clutch device. Furthermore, adverse wear phenomena can occur with such a clutch based on friction forces.

[0006] EP 1 981 371 B1 shows a furniture drive with a drive unit and a slip clutch, the slip clutch being designed such that it decouples the drive unit and the ejector from one another when a predetermined torque is exceeded. The slip clutch operates on the basis of the diameter of a wrap spring, as a result of which the clutch intensity for this type of clutch device is disadvantageously difficult to adjust, for example by completely replacing the wrap spring. EP 2 086 372 B1 shows a furniture drive with a clutch device for at least temporarily transmitting a force to an actuating arm, the clutch device being designed in the form of a sleeve freewheel. The clutch intensity for this type of clutch device is disadvantageously not adjustable.

[0007] The object of the 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 having the features of claim 1, as well as a piece of furniture comprising such a furniture drive. Advantageous embodiments of the invention are defined in the dependent claims.

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

[0010] Closed position of the furniture part.

[0011] The furniture drive has a coupling device with at least one drive part and at least one output part rotatable relative thereto. A drive of the furniture drive can act on the drive part. The output part can be connectable or connected to an actuating arm. The furniture drive can have multiple coupling devices. A coupling device can also have multiple drive parts and multiple output parts, for example in a series circuit.

[0012] It is provided that a coupling intensity between the at least one drive part and the at least one output part can be adjusted using an adjusting device. The coupling intensity can be adjusted between a substantially rigid coupling and a substantially suspended force-transmitting connection between the at least one drive part and the at least one output part.

[0013] For the design of the coupling device, it is provided that the at least one drive part and the at least one output part are arranged at a distance from one another to form a gap. The at least one drive part and the at least one output part can, for example, be arranged next to one another along a common axis at a predetermined or predeterminable distance and form a gap due to the spaced arrangement.

[0014] It is intended that the gap is filled with a magnetorheological medium that can be influenced by a magnetic field.

[0015] The adjusting device is designed to adjust the coupling intensity, wherein for this purpose it has a device for generating a magnetic field for the magnetic polarization of the magnetorheological medium.

[0016] A magnetorheological medium 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. This allows a magnetorheological medium to undergo a controlled transition from a fluid-like to an essentially solid state. This allows a wear-free coupling intensity to be adjusted simply by adjusting the device for generating a magnetic field.

[0017] The furniture drive can advantageously be coupled and uncoupled to an actuating arm using the coupling device with a coupling intensity corresponding to the polarization of the magnetorheological medium.

[0018] The coupling device can be used, for example, as an overload clutch, as a freewheel clutch, for coupling a damping device or for coupling a drive.

[0019] The device for generating a magnetic field for polarizing the magnetorheological medium can comprise at least one electromagnet with an energizable coil. By adjusting the current flowing through the coil, a coupling intensity can be adjusted depending on the polarization of the magnetorheological medium. Preferably, the energizable coil is arranged stationary in the furniture drive. The at least one drive part and at least one output part can each be arranged rotatably relative to the coil in the furniture drive.

[0020] It should not be excluded that the device for generating a magnetic field for polarizing the magnetorheological medium comprises several electromagnets and / or at least one permanent magnet.

[0021] If the drive part and the output part are arranged on an axis running through a coil of a device for generating a magnetic field, a magnetic field and thus a polarization of the magnetorheological medium can occur along the axis. The drive part can be made of a magnetizable material and protrude at least partially into an inner region of the coil. A magnetic flux generated by the energized coil can be guided by the drive part into a region of the gap. Preferably, a drive shaft protruding axially from the drive part can protrude into an inner region of the coil for coupling to a drive of the furniture drive.

[0022] The drive part can have a bearing shaft that projects axially from the drive part to guide the output part. The output part can be rotatably mounted on the drive part, for example, via a ball bearing arranged on the bearing shaft that projects axially from the drive part. The bearing shaft is preferably made of a magnetizable material to conduct a magnetic flux.

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

[0024] The drive part can be disk-shaped, at least in sections. A disk-shaped portion of the drive part can be arranged facing the gap. In other words, a disk-shaped portion of the drive part can form a boundary surface of the gap.

[0025] To form an open U-profile cross-section, the drive part can have an axial projection at least in sections. In particular, the drive part can be disk-shaped at least in sections and have an axial projection projecting therefrom, for example a circumferentially axially projecting web, at least in sections. The axial projection or web can preferably be arranged in a radially located edge region of the drive part. The axial projection or web can form a boundary surface of the gap.

[0026] The driven part can be at least partially disc-shaped. In this case, a disc-shaped section of the driven part can be arranged facing the gap. In other words, a disc-shaped section of the driven part can form an interface of the gap.

[0027] In an advantageous embodiment, the drive part can have an axial projection at least in sections to form an open U-shaped cross-section, and the output part can be arranged at least partially in the U-shaped cross-section of the drive part. The gap can be essentially delimited by the drive part and the output part.

[0028] The drive part can at least partially radially enclose the output part.

[0029] The gap can be formed at least radially by the arrangement of the drive part to the driven part.

[0030] Advantageously, a seal for enclosing the magnetorheological medium is arranged radially between the drive part and the driven part. If the drive part and the driven part are arranged on an axis running through a coil of a device for generating a magnetic field, a magnetic field and thus a polarization of the magnetorheological medium can occur axially. The effective area of ​​the gap can be maximized by a radial arrangement of a seal. The drive part and / or the driven part can have, at least in sections, a structured surface facing the gap in order to form a positive connection with the magnetorheological medium. The structured surfaces can in particular have an axial offset from one another. The structured surfaces can be designed in the form of radial webs and radial recesses in the drive part and / or in the driven part.Due to the structured surfaces, shear forces can act on the magnetorheological medium when the output part rotates relative to the drive part.

[0031] The furniture drive can have an electric motor for driving an actuating arm, wherein an actuating arm can be coupled and uncoupled to the electric motor with the coupling device according to a coupling intensity.

[0032] For connection to a drive of the furniture drive, the drive part can have a drive shaft that protrudes axially from the center of the drive part. The drive part can be rotatably mounted in the furniture drive, for example, via a ball bearing arranged on the drive shaft that protrudes axially from the center of the drive part.

[0033] If the furniture drive has an electric motor for driving the actuating arm, and the actuating arm can be coupled and uncoupled from the electric motor using the coupling device according to a coupling intensity, the electric motor can be operated as a generator to dampen the movement of an actuating arm connected to the output part. Damping the movement of an actuating arm may be desirable, particularly in an end range of a limited movement of the actuating arm.

[0034] The furniture drive advantageously has a control system for the adjustment device. If the adjustment device for adjusting the clutch intensity has a device for generating a magnetic field with at least one electromagnet with an energizable coil, the control system can control and / or regulate the strength of the current flowing through the coil. Control and / or regulation can, for example, take place as a function of an actuating angle of an actuating arm connected to the output part. For this purpose, an angle of rotation of the output part relative to a housing of the furniture drive can be detected, for example, using an angle sensor and fed to the control system. An electric motor of the furniture drive can also be controllable by the control system.

[0035] The furniture drive can have a mechanical energy storage device, which is or can be connected to an actuating arm connected to the output part. The coupling device can be used to exert a force from the energy storage device and / or a force generated by the electric motor on the actuating arm. For example, the mechanical energy storage device can be used to compensate for the weight of a furniture part connected to the actuating arm, and the electric motor can be used to drive or dampen a movement of the furniture part.

[0036] Protection is also sought for a piece of furniture with at least one furniture drive as described above. At least one movable part of the furniture can be or is connectable to an actuating arm of the furniture drive connected to the output part.

[0037] The piece of furniture may comprise a furniture body with at least one wall, wherein the furniture drive, in an installed position, can be arranged or disposed substantially entirely in a recess in a wall of the furniture body. Exemplary embodiments of the invention are discussed with reference to the figures. They show:

[0038] Fig. 1a and 1b a perspective view and a sectional view of a first embodiment of a furniture drive,

[0039] Fig. 2 is an exploded view of an embodiment of a

[0040] Coupling device,

[0041] Fig. 3a and 3b are a perspective view and a sectional view of an embodiment of a coupling device,

[0042] Fig. 4a and 4b sectional views of a coupling device and parts of a coupling device,

[0043] Fig. 5a and 5b sectional views of parts of a coupling device,

[0044] Fig. 6 is a sectional view of a second embodiment of a furniture drive,

[0045] Fig . 7a and 7b perspective views of a piece of furniture , and

[0046] Fig . 8 is a schematic representation of a

[0047] Furniture drive with a control system.

[0048] Figure 1a shows a perspective view of a first embodiment of a furniture drive 1. Figure 6 shows a side view of a sectional view of a second embodiment of a furniture drive 1, wherein this view shows an actuating arm 2 connected to the furniture drive. It goes without saying that an actuating arm 2 can also be provided for the first embodiment of the furniture drive 1 shown in Figure 1a.

[0049] Figure 1a shows a furniture drive 1 for an actuating arm 2, comprising a housing 25 and a coupling device 3 with a receiving area 26 for an actuating arm 2. As can be seen in the sectional view of Figure 1b, the furniture drive 1 comprises at least one drive part 4 and at least one output part 5 rotatable relative thereto.

[0050] The at least one drive part 4 and the at least one output part 5 are arranged at a distance from one another to form an axial and radial gap 6. The gap 6 is filled with a magnetorheological medium 7, shown hatched.

[0051] With an adjustment device which has a device for generating a magnetic field 8, a coupling intensity between the at least one drive part 4 and the at least one output part 5 can be adjusted, wherein a coupling intensity can be adjusted via the magnetic polarization of the magnetorheological medium 7.

[0052] An actuating arm 2 can be coupled and uncoupled to the furniture drive 1 using the coupling device 3 with a coupling intensity corresponding to the polarization of the magnetorheological medium 7.

[0053] In the embodiment shown, the device for generating a magnetic field 8 for polarizing the magnetorheological medium 7 comprises at least one electromagnet with an energizable coil 9. As shown, the energizable coil 9 is arranged stationary in the furniture drive 1.

[0054] Figure 2 shows an exploded view of an embodiment of a coupling device 3. Figures 3a and 3b show a perspective view and a sectional view of a coupling device 3. Figures 4a and 4b as well as 5a and 5b show sectional views of a coupling device and parts of a coupling device. The figures show that the drive part 4 has a drive shaft 10 which projects axially from the drive part 4 for coupling to a drive of the furniture drive 1 and which projects into an inner region of the coil 9, as shown. The drive part 4 can be rotatably mounted in the housing 25 of the furniture drive 1 via the axially projecting drive shaft 10, for example via ball bearings.

[0055] In the embodiment shown, the drive part 4 is at least partially disc-shaped and has a circumferential axial projection 12 in an edge region to form an open U-profile cross-section (see in particular Figures 2 and 4b).

[0056] The drive part 4 further comprises a bearing shaft 12 that projects axially centrally from the drive part 4 to guide the output part 5. The output part 5 can be rotatably mounted thereon, for example via ball bearings.

[0057] In the embodiment shown, the output part 5 is at least partially disc-shaped.

[0058] As can be seen particularly in Figures 1b and 4b, the drive part 4 and the driven part 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.

[0059] Due to the open U-profile cross-section of the drive part, the output part 5 can be arranged at least partially in the U-profile cross-section of the drive part 4. The drive part 4 can at least partially radially enclose the output part 5. Radial seals 13, 14 can be arranged between the drive part 4 and the output part 5, whereby the volume formed between the drive part 4 and the output part 5 for the magnetorheological medium 7 can be sealed. The volume of the magnetorheological medium 7 is illustrated, for example, in the exploded view in Figure 2.

[0060] To fill the volume formed between the drive part 4 and the driven part 5 for the magnetorheological medium 7, ventilation openings 15 can be provided in the driven part.

[0061] In Figure 2 it can be seen that the drive part 4 and the driven part 5 can have, at least in sections, a structured surface facing the gap 6 with webs 16 and recesses 17 in order to form a positive connection with the magnetorheological medium 7.

[0062] Figure 6 shows a second embodiment of a furniture drive 1. The furniture drive can have a coupling device 3 as described above. In this embodiment, the coupling device 3 is connected by a rod assembly 28 to an actuating arm 2 for a movable furniture part 21 (see Figures 7a and 7b). The rod assembly 28 can be connected, for example, via a gear wheel and a rack to the connecting region 26 hidden in the figure.

[0063] The actuating arm 2 can be coupled and uncoupled to the furniture drive 1 using the coupling device 3 with a coupling intensity corresponding to the polarization of the magnetorheological medium 7.

[0064] In the second embodiment shown, the furniture drive 1 has an electric motor 18 for driving an actuating arm 2 connected to the output part 5. The actuating arm 2 can be coupled to and uncoupled from the electric motor 18 using the coupling device 3 according to a coupling intensity.

[0065] Furthermore, the furniture drive 1 in the second embodiment has a mechanical energy accumulator 19, which is connected to the actuating arm 2 via a lever. Depending on the coupling intensity, the coupling device 3 can exert a force from the energy accumulator 19 and / or a force generated by the electric motor 18 on the actuating arm 2 connected to the output part 5.

[0066] The electric motor 18 can also be operated as a generator to dampen the movement during a movement of the actuating arm 2 - in particular in an end region of a limited movement of the actuating arm 2.

[0067] Figures 7a and 7b show an embodiment of a piece of furniture 20 with two furniture drives 1 as described above. A movable furniture part 21 in the form of a furniture flap of the piece of furniture 20 is connected to the actuating arms 2 of the furniture drives 1.

[0068] As shown, the piece of furniture 20 has a furniture body 22 with at least one wall 23, wherein a furniture drive 1 in each case can be arranged in an installation position shown in Figure 7b essentially completely in a recess 24 in a wall 23 of the furniture body 22.

[0069] Figure 8 shows a schematic view of a furniture drive 1 with a controller 29 for the device for generating a magnetic field 8 of the adjustment device. If the adjustment device for adjusting the clutch intensity has a device for generating a magnetic field 8 with at least one electromagnet with a coil 9 that can be energized as described above (see, for example, Figure 1b), the controller 29 can control and / or regulate the current intensity of the current flowing through the coil 9. Control and / or regulation can, for example, take place as a function of an actuating angle of an actuating arm 2 connected to the output part. For this purpose, an angle of rotation of the output part 5 relative to a housing 25 (see, for example, Figure 1a or Figure 6) of the furniture drive 1 can be detected and fed to the controller 29. An electric motor 18 of the furniture drive can also be controllable by the controller 29.The control 29 can be integrated into the furniture drive 1 or can be designed separately from it.

[0070] Reference symbol list

[0071] 1 furniture drive

[0072] 2 actuating arms

[0073] 3 Coupling device

[0074] 4 drive part

[0075] 5 Stripping section

[0076] 6 gap

[0077] 7 magnetorheological medium

[0078] 8 Device for generating a magnetic field

[0079] 9 coil

[0080] 10 Drive shaft

[0081] 11 Bearing shaft

[0082] 12 lead

[0083] 13 Seal

[0084] 14 Seal

[0085] 15 Ventilation opening

[0086] 16 jetty

[0087] 17 Recess

[0088] 18 electric motor

[0089] 19 mechanical energy storage

[0090] 20 pieces of furniture

[0091] 21 furniture part

[0092] 22 Furniture body

[0093] 23 Wall

[0094] 24 recess

[0095] 25 housings

[0096] 26 Connection area

[0097] 27 gearboxes

[0098] 28 rods

[0099] 29 Control

[0100] 30 sensors

Claims

Patent claims Furniture drive (1) for an actuating arm (2) with a coupling device (3) for an actuating arm (2) with at least one drive part (4) and at least one output part (5) rotatable relative thereto, characterized in that a coupling intensity between the at least one drive part (4) and the at least one output part (5) can be adjusted using an adjusting device, wherein the at least one drive part (4) and the at least one output part (5) are arranged at a distance from one another 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 adjusting device for adjusting the coupling intensity has a device for generating a magnetic field (8) for the magnetic polarization of the magnetorheological medium (7).Furniture drive according to the preceding claim, wherein an actuating arm (2) connected to the output part (5) is connected to the coupling device (3) with a polarization corresponding to the magnetorheological medium (7). Coupling intensity can be coupled and uncoupled to the furniture drive (1). Furniture drive according to the preceding claim, wherein the Device for generating a magnetic field (8) for Polarization of the magnetorheological medium (7) comprises at least one electromagnet with an energizable coil (9), wherein preferably the energizable coil (9) is arranged stationary in the furniture drive (1). Furniture drive according to the preceding claim, wherein the Drive part (4) made of a magnetizable material and projects at least partially into an inner region of the coil (9), wherein preferably a drive shaft (10) projecting axially from the drive part (4) projects into an inner region of the coil.

5. Furniture drive according to one of the preceding claims, wherein the drive part (4) for guiding the output part (5) has a bearing shaft (12) projecting axially centrally from the drive part (4), wherein the bearing shaft (12) is preferably made of a magnetizable material.

6. Furniture drive according to one of the preceding claims, wherein the drive part (4) and the driven part (5) are arranged adjacent to one another along a common axis of rotation and the gap (6) is formed at least axially.

7. Furniture drive according to one of the preceding claims, wherein the Drive part (4) is at least partially disc-shaped.

8. Furniture drive according to one of the preceding claims, wherein the drive part (4) has an axial projection (12) at least in sections to form an open U-profile cross-section, preferably in an edge region.

9. Furniture drive according to one of the preceding claims, wherein the Output part (5) is at least partially disc-shaped.

10. Furniture drive according to one of the preceding claims, wherein the drive part (4) has an axial projection (12) at least in sections to form an open U-profile cross-section and the output part (5) has at least is partially arranged in the U-profile cross-section of the drive part (4).

11. Furniture drive according to the preceding claim, wherein the drive part (4) at least partially radially encloses the output part (5).

12. Furniture drive according to one of the preceding claims, wherein the gap (6) is formed at least radially.

13. Furniture drive according to the preceding claim, wherein at least one radial seal (13, 14) is arranged between the drive part (4) and the output part (5).

14. Furniture drive according to one of the preceding claims, wherein the drive part (4) and / or the output part (5) have at least in sections a structured surface facing the gap (6) to form a positive connection with the magnetorheological medium (7).

15. Furniture drive according to one of the preceding claims, wherein the furniture drive (1) has an electric motor (18) for driving an actuating arm (2) connected to the output part (5), and an actuating arm (2) can be coupled and uncoupled from the electric motor (18) with the coupling device (3) according to a coupling intensity.

16. Furniture drive according to the preceding claim, wherein the furniture drive (1) has a mechanical energy storage device (19) which is connectable or connected to an actuating arm (2) connected to the output part (5), wherein with the coupling device (3) according to a coupling intensity on an actuating arm (2) connected to the output part (5) a force from the energy storage device (19) and / or a force caused by the electric motor (18) can be exerted. Furniture drive according to one of the preceding claims, wherein the Drive part (4) for connection to a drive of the furniture drive (1) has a drive shaft (10) projecting axially centrally from the drive part (4). Furniture drive according to one of the preceding claims, wherein the Furniture drive has an electric motor (18) for driving an actuating arm (2) and an actuating arm (2) with the coupling device (3) according to a Coupling intensity can be coupled and uncoupled to the electric motor (18), wherein the electric motor (18) is used during a movement of an actuating arm (2) - in particular in an end region of a limited movement of the actuating arm (2) - to dampen the Movement is operable as a generator. Furniture (20) with at least one furniture drive (1) according to one of the preceding claims, wherein at least one movable furniture part (21) of the furniture (20) is connectable or connected to an actuating arm (2) of the furniture drive (1). Furniture (20) according to the preceding claim, wherein the furniture (20) has a furniture body (22) with at least one wall (23), wherein the furniture drive (1) in an installed position can be or is arranged substantially completely in a recess (24) in a wall (23) of the furniture body (22).

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