Height-adjustable office furniture

Abstract

A height-adjustable office furniture comprising a table top, at least one height adjustable leg unit and a drive unit to drive adjustment of the height of the leg, a drive control system configured to control and power the drive unit and an anti-collision system connected to the drive control system and configured to detect when movement of the table top along the vertical direction Z is blocked. A resilient element is provided in the connection between the drive unit and the table top, the resilient element defining a suspension travel extending along a vertical direction Z to reduce vibrations.

Claims

1. A height-adjustable office furniture comprising: a table top having a top surface and a bottom surface opposite to the top surface; at least one height adjustable leg unit connected to the table top, wherein the at least one leg unit is provided with a drive unit to drive adjustment of the height of the leg, wherein a resilient element is provided in the connection between the drive unit and the table top, the resilient element defining a suspension travel of the table top extending along a vertical direction Z; the office furniture further comprising a drive control system configured to control and power the drive unit; and an anti-collision system connected to the drive control system and configured to detect when movement of the table top along the vertical direction Z is blocked.

2. The height-adjustable office furniture according to claim 1 further comprising a support frame connected to the bottom surface of the table top, wherein the at least one height adjustable leg unit is connected to the table top through the support frame.

3. The height-adjustable office furniture according to claim 2 wherein the resilient element is provided between the table top and a support frame.

4. The height-adjustable office furniture according to claim 2, wherein a plurality of spacers is placed between the table top and the support frame.

5. The height-adjustable office furniture according to claim 4, wherein the spacers are made of a plastic material or metal.

6. The height-adjustable office furniture according to claim 3, wherein the resilient element is a first resilient element and wherein a second resilient element is provided between the drive unit and the support frame.

7. The height-adjustable office furniture according to claim 5 comprising a guard for receiving the second resilient element with the drive unit connected thereto, the guard preventing compression of the second resilient element during assembly of the office furniture.

8. The height-adjustable office furniture according to claim 7, wherein the guard is made of a material that is harder than the material of the second resilient element.

9. The height-adjustable office furniture according to claim 6, wherein the drive unit comprises a spindle plate and wherein the second resilient element supports the spindle plate.

10. The height-adjustable office furniture according to claim 9, wherein the second resilient element is ring shaped with a circumferential groove along its outer circumferential surface to support the spindle plate of the drive unit.

11. The height-adjustable office furniture according to claim 6, wherein the first and/or second resilient elements are made of rubber.

12. The height-adjustable office furniture according claim 1, wherein the anti-collision system comprises a sensor connected to the drive control system, wherein the sensor can measure vertical acceleration and/or deceleration.

13. The height-adjustable office furniture according to claim 12, wherein the sensor is provided at the table top.

14. The height-adjustable office furniture according to claim 13, wherein the sensor is provided at the bottom surface of the table top.

15. The height-adjustable office furniture according to claim 1, configured to adjust the height with an average speed of at least 2 cm/s, preferably at least 4 cm/s.

16. The height-adjustable office furniture according to claim 1, wherein the noise produced by the height adjustment of the desk is less than 50 dB, preferably less than 45 dB, and more preferably less than 40 dB.

17. The height-adjustable office furniture according to claim 1, wherein the table top is made of a light-weight material such as wood.

18. A height adjustable leg unit for the height-adjustable office furniture according to claim 1.

19. A frame structure for the height-adjustable office furniture according to claim 1, the frame structure comprising a support frame configured to support a table top; at least one height adjustable leg unit connected to the support frame, wherein the at least one leg unit is provided with a drive unit to drive adjustment of the height of the leg, wherein a resilient element is provided in the connection between the drive unit and the support frame, the resilient element defining a suspension travel of the table top extending along a vertical direction Z; the frame structure further comprising a drive control system configured to control and power the drive unit; and configured to be connected to an anti-collision system.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0024] Embodiments will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts. In the drawings, like numerals designate like elements. Multiple instances of an element may each include separate letters appended to the reference number. For example, two instances of a particular element “20” may be labeled as “20a” and “20b”. The reference number may be used without an appended letter (e.g. “20”) to generally refer to an unspecified instance or to all instances of that element, while the reference number will include an appended letter (e.g. “20a”) to refer to a specific instance of the element.

[0025] FIG. 1A shows a perspective view of a first embodiment of height-adjustable office furniture.

[0026] FIG. 1B shows a bottom view of the height-adjustable office furniture in FIG. 1A.

[0027] FIG. 1C shows a schematic diagram of the components in the height adjustable office furniture in FIGS. 1A and 1B.

[0028] FIG. 1D shows a cross-sectional view of the height-adjustable office furniture in FIGS. 1A and 1B.

[0029] FIGS. 1E and 1F show a cross-sectional view of two details of the height-adjustable office furniture as indicated in FIG. 1D.

[0030] FIG. 2A shows a perspective view of a leg unit of the height-adjustable office furniture in FIG. 1A.

[0031] FIG. 2B shows a detail of the leg unit as indicated in FIG. 2A.

[0032] FIG. 2C shows a cross-sectional side view of a mounting stud.

[0033] The figures are meant for illustrative purposes only, and do not serve as restriction of the scope or the protection as laid down by the claims.

DESCRIPTION OF EMBODIMENTS

[0034] The following is a description of certain embodiments of the invention, given by way of example only and with reference to the figures.

[0035] FIG. 1A shows a perspective view of a first embodiment of a piece of height-adjustable office furniture 1. The piece of height-adjustable office furniture 1 is a desk, which has a table top 2 with a top surface 21 and a bottom surface 22, two height adjustable leg units 3, a support frame 4 and a control panel 71 for adjusting the height of the desk. The top surface 21 of the table top 2 is arranged opposite to the bottom surface 22 and the support frame 4 is engaged to the table top 2 at the bottom surface 22. The height adjustable leg units 3 are connected to each other and the table top 2 through the support frame 4.

[0036] FIG. 1B schematically shows a bottom view of the height adjustable office furniture 1 in FIG. 1A. The office furniture 1 comprises a central drive control system 7 and an anti-collision system 8, which are both indicated only schematically. The drive control system 7 is configured to control a height adjustment of both the leg units 3 the office furniture 1. The drive control system 7 can be connected to a power source (not shown). The anti-collision system 8 includes a sensor 9 (schematically indicated) that can measure vertical acceleration, and which is operatively connected to the drive control system 7 and configured to detect when movement of the table top 2 along the vertical direction Z is slowed down or blocked. The sensor 9 is preferably directly mounted onto the table top where the vibrations are optimally reduced, but it will be understood that alternatively the sensor 9 might also be mounted to the support frame 4. The drive control system 7 is configured to stop height adjustment of the office furniture 1 when the vertical movement to adjust the height is blocked.

[0037] The drive control system 7 is operatively connected to the control panel 71 which can be operated by a user to adjust the desk in height. The drive control system 7 can adjust the height of the desk with an average speed of 4 cm/s. During such height adjustment a noise having a strength of maximum 45 dB is created. This combination of relatively high adjustment speed with low volume noise can be created due to a suspension travel of the table top in its connection to the height adjustable leg units 3.

[0038] FIG. 1C shows a schematic diagram of the components in the height adjustable office furniture 1. The table top 2 with top surface 21 and bottom surface 22 is indirectly connected to a drive unit 6 via the support frame 4. A first resilient element 25 is provided in the connection between the table top 2 and the support frame 4. Hence the first resilient element 25 is automatically also provided in the connection between the table top 2 and the drive unit 6. The first resilient element 25 is limited by a spacer 27 that ensures a minimum distance between the table top 2 and support frame 4 is always provided. The first resilient element 25 and spacer 27 define a suspension travel Δz of the table top 2 extending along the vertical direction Z.

[0039] The drive unit 6 includes a motor 61 and a spindle drive 64. After being connected to a power supply, the motor 61 drives rotation of a spindle drive 64 that extends through the leg unit 3 and actuates a mechanical lift system within the leg unit 3. The drive unit 6 is connected to the frame 4 using a second resilient element 65, limited in its movement by a guard 66.

[0040] FIG. 1D shows a front view of the height-adjustable office furniture 1 according to the invention. The table top 2 is resiliently mounted to the support frame 4. This means that the table top 2 and support frame 4 are not in direct contact with each other over their full length, but only at a limited number of positions. The connection between the table top 2 and support frame 4 is provided by a plurality of corner connections 23 and center connections 24.

[0041] FIG. 1E shows a cross-sectional detail of a corner connection 23. Near the edges of the table top 2, the support frame 4 extends substantially parallel to the table top 2. The bottom surface 22 of the table top 2 is connected to the frame using a pair of screws 42. The screws extend through part of the support frame 4 and into the table top 2. Around the screws 42, first resilient elements 25 are provided. The first resilient elements 25 are made of rubber and provide isolation of the table top 2 from the support frame 4. The first resilient element 25 is ring shaped and has a circumferentially extending receptacle 26 for receiving the support frame 4. It will be understood that dependent on the shape of the support frame 4 a varying number of screws 42 may be used.

[0042] FIG. 1F shows a cross-sectional detail of a center connection 24. The center screw 24 is provided with a spacer 27 that is arranged between the table top 2 and the support frame 4. The spacer 27 is shaped as a ring and is made of a plastic material. A number of center screws 24 are provided between the table top 2 and the support frame 4 to ensure a stable support. It will be understood that dependent on the size of the desk, just a few or more screws 44 and spacers 27 may be provided. Rubber rings 28 are provided between the table top 2 and the support frame 4.

[0043] The first resilient elements 25 define the suspension travel Δz extending along the vertical direction Z. The first resilient elements 25, aided by the rubber rings 28, thereby prevent vibrations in the support frame 4 from being passed on to the table top 2. This leads to a reduction of the noise that is generated when the office furniture 1 is adjusted in height. In addition, the reduction in vibrations of the table top 4 increase the accuracy of the sensor 9 in the anti-collision system 8. In comparison to systems without a resilient element, the accuracy of the sensor can be increased by approximately 20%. The corner connections 23 and central connections 24 should be considered in all respects only as illustrative and not restrictive. In embodiments, only one type of connection may be provided with both a resilient element and a spacer integrated in the same connection.

[0044] FIG. 2A shows a perspective view of a leg unit 3 of the office furniture 1. The leg unit 3 includes a telescopic type leg having leg segments 31, 32, and 33. The spindle drive 64 is extending through the leg unit 3, which provides the mechanical lift system within the leg unit 3. The leg unit has a top end 34 and a bottom end 35. The top end 34 is provided with a mounting plate 36. The mounting plate has two mounting flanges 37 with openings 38. Bolts may be provided through these openings to connect the leg unit 3 to the support frame 4. It will be understood though that in other embodiments, the leg units 3 may also be directly connected to the table top 2. The mounting plate 36 is further provided with a deepened portion 39 that provides space for a drive unit 6.

[0045] FIG. 2B shows a detailed view of the drive unit 6 and mounting plate 36 of the leg unit 3. The drive unit 6 includes a motor 61 a spindle plate 62 and a spindle drive 64. The spindle plate 62 connects to the spindle drive 64 and carries the other elements of the drive unit 6. After being connected to a power supply, the motor 61 drives rotation of a spindle drive 64 that extends through the leg segments 31, 32, 33 and actuates the mechanical lift system within the leg unit 3. The spindle plate 62 is connected to the frame using a plurality of mounting studs 63.

[0046] FIG. 2C shows a simplified detail of the connection of the drive unit 6 to the mounting plate 36 through the mounting studs 63. The spindle plate 62 is spaced at a distance of the mounting plate 36 using a second resilient element 65 that supports the spindle plate 62. The second resilient element 65 is a rubber ring with a circumferential groove 67 along its outer circumferential surface. The spindle plate 62 is supported within the circumferential groove 67.

[0047] The second resilient element 65 is surrounded by a guard 66 which ensures that the second resilient element 65 is not fastened too tight during assembly in a way that the resilient properties of the second resilient element 65 would not have any effect. The guard 66 is made of steel but also could be made of another metal, metal alloy, or even of a plastic material, as long as the guard 66 has a higher hardness than the rubber of the second resilient element 65.

[0048] The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. It will be apparent to the person skilled in the art that alternative and equivalent embodiments of the invention can be conceived and reduced to practice. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.