ADJUSTABLE FURNITURE

FIELD OF THE INVENTION

This invention relates to a height-adjustable furniture having one or more adjusting mechanisms for adjusting parts of the furniture, e.g. table tops, seats, bed boards and the like, in a number of height and/or tilt positions.

BACKGROUND OF THE INVENTION

Development of adjustable furniture has in recent many years been concentrated on provision of adjusting mechanisms making it easy to switch position of the furniture e.g. a table, a chair or a bed. In such a manner, problems resulting from maintaining a body position over longer time are avoided. Much is done and much is invested in order that personnel do not sustain permanent harm to the musculoskeletal system resulting from inappropriate working postures. In the industry, regular evaluation (Workplace Risk Assessment) is performed regarding the workplaces, and often inspections are performed by ergo therapists and physiotherapists, who go over the layout of each individual workplace. The employees themselves are also aware that their posture during working hours is important.

Accordingly, many such constructions are known, whereby it is possible to adjust the height as well as the tilt of e.g. a table with one or more tabletops, and equally well for the seat, the backrest and the armrest of a chair. Other examples are beds in hospitals and in private use, whereby the bed should support a number of different sitting and horizontal positions, preferably without too much physical work for the employees or relatives.

For the well-known devices adjustments are made, whereby the user activates the adjustment mechanisms, which could be designed in countless ways and be operated in a purely mechanic way or by means of small servomotors.

Moreover, it is generally known to adjust furniture to individually adapted positions, which the user can switch between, e.g. by keying in personal codes in the adjusting

mechanisms. This is especially applied to the automobile industry in order to switch between different positions of seats, etc.

However, the users' options to modify the settings of the furniture are not utilized to their full potential, because the user typically settles for e.g. standing or sitting at a table or on a chair, and typically changes would not be undertaken or at a maximum one or two times during one working day. The useful effect of the adjustable furniture would therefore fail to appear, and accordingly the user still risks being harmed due to extended hours (monotonous repetitive work) in the same posture.

US 5,224,429 describes a height-adjustable table, or workstation, wherein adjustments are handled by drive motors being controlled by a controller, such as a microprocessor.

A user entering parameters for a number of desired height locations can program the controller. Moreover, making a sequence of the programmed locations is a user-dependent rather than user-independent process because each sequence step requires confirmation by the user before execution.

However, problems related to lack of posture changes are solved according to the invention as adjustable furniture of the kind described above have their adjusting mechanisms arranged to be able to bring the furniture into optional positions through user-independent control of the mechanisms. The changes are minor and happen very slowly and preferably unnoticed by the user.

The initiative to modify position is now moved from the user to the user-independent control of the mechanisms, and accordingly changes are automatically taking place.

The user-independent control of the adjusting mechanisms can be undertaken in sev- eral principally different ways: especially, but not exhaustively, positions taken in a random sequence, positions chosen from a selection of positions being previously accepted by the user as desired positions, and a fixed sequence of positions. Moreover, it would be possible to vary a parameter covering the duration of each position and the changeover time. Similarly, the tilt angle and the deflection of the adjustable parts could be varied from time to time.

If a user-independent change of position proves inappropriate in a certain work situation, use could be made of a built-in actuation mechanism according to the invention, whereby the user can take over control of his/her furniture in order to halt its changeover or switch to a subsequent position.

The control unit could preferably be comprised by a control circuit with an actuator, e.g. a servomotor, to drive the adjusting mechanisms.

The control unit according to the invention could comprise a computerized control, wherein a pre-entered program manages switching between the different positions of the furniture. Furthermore, the control unit according to the invention could include a sensor evaluating whether the furniture is in use and can, in the affirmative, keep the switching program active. Alternatively, the control unit could be activated and deactivated by the user by means of a time switch.

In order to effectively counteract RSI (Repetitive Strain Injury) it is important to frequently change positions and thereby also the muscles used by the user in each position. This is obtained by even small changes (a few centimeters at a time) - and is almost not recognized by the user.

Furthermore, the invention could include a warning mechanism, which is activated and issues a signal (sound, light, vibrations or the like) in advance of any position change.

The control unit could be applied to new furniture as well as furniture in use, wherein the current drive mechanisms could optionally be reused wholly or in part.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the invention will hereafter be explained in details and with reference to the accompanying drawing, wherein

Fig. 1 shows an adjustable table according to the invention, and Fig. 2 is a diagram showing a control circuit for a position-adjustable table according to the invention.

DETAILED DESCRIPTION

Fig. 1 shows a table 1 comprising two tabletops S ₁ and S ₂ being connected via a frame 3 to a foot 2, supported on a substrate.

The tabletop S ₁ can be moved up and down by activating a cylinder/piston unit 4. The tabletop S ₂ can be moved up and down by a cylinder/piston unit 7 and moreover be pivoted/tilted around a pivot point 9 by being activated by a cylinder/piston unit 6.

The cylinder/piston units 4, 6, 7 are being activated by a control unit 5, resulting in the settings of the tabletops being amended.

As shown diagrammatically in Fig. 2, each of the cylinder/piston units could be managed by a set of data, which is supplied to the control unit 5 in the form of a computer program.

Furthermore, referring to Figs. 1 and 2, a sensor 10 is provided on the table 1 and serves the purpose of informing the controller unit 5 if a user uses the table 1. If a user is not present, the controller 5 assumes a standby position.