AU745636B2

AU745636B2 - Adjustable bed base

Info

Publication number: AU745636B2
Application number: AU12608/00A
Authority: AU
Inventors: Siegbert Hartmann
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-09-21
Filing date: 1999-09-20
Publication date: 2002-03-28
Anticipated expiration: 2019-09-20
Also published as: EP1115311A1; DE19843259C1; DE59903060D1; AU1260800A; EP1115311B1; TR200003849T2; WO2000016663A1; ATE225624T1

Abstract

The invention relates to a bed base which can be adjusted by means of an electric motor. The inventive bed base is comprised of a frame having two longitudinal and transversal spars, of at least one pivotally mounted foot or back section having an inner frame and an adjusting drive arranged underneath the frame. The bed base also comprises an adjusting mechanism with an adjusting lever (4) which is linked to the frame, which is situated underneath the inner frame and which rests thereon. The bed base also has a lever arm (5) which is connected to the adjusting lever such that it cannot be rotated and which is connected to the adjusting drive via a coupling element. Said bed base is constructed in a simple manner and of few components and can be economically produced. To this end, the coupling element is comprised of a rope-, strap-, or chain-shaped traction means (6) and the adjusting drive (1) drives a shaft (7) on which the one winding device for the traction means (6) is arranged.

Description

HARTMANN Siegbert 2361/420-18 Neuer Kamp 71 D-32584 Lhne ADJUSTABLE BED BASE The invention relates to an adjustable bed base according to the precharacterising portion of the first claim.

From DT 24 20 598 Al a device for pivoting components that can be raised, on mattress frames, is known, said device comprising adjusting levers, which underneath the inner frame, rest on said inner frame, with the adjusting levers being interconnected via a common drive shaft. A lever arm is arranged on said drive shaft so that it cannot be rotated, said lever arm being connected to the adjusting drive via a rod-shaped coupling element, said adjusting drive in turn being arranged so as to be articulated, along a transversal axis determined in the frame.

This known construction is associated with the disadvantage that its design is very expensive, requiring a large number of different components and that, if an uneven load acts on the resting surface, very considerable torsional moments can occur in the drive shaft for the adjusting levers. Consequently, either the drive shaft, or else the inner frame of the bed base has to be built so as to be relatively massive and heavy, otherwise said the bed base would be subject to very considerable torsional buckling in the case of one-sided loading. Furthermore, to generate a lift and push movement, the massive coupling element requires the presence of threaded spindles or spindle nuts which from a mechanical point of view are expensive to produce, so that the entire adjusting mechanism is extremely production-intensive and cost-intensive, providing little flexibility.

Furthermore from US A-4 095 296 an adjustable bed base is known which uses a traction means for load transmission, and in particular for load deflection. To this effect, the traction means is not shortened by winding but instead always remains the same length. The bed base comprises an adjusting drive which for angle adaptation has to be pivotally coupled to a bed frame because it mechanically acts directly upon a lever arm of an adjusting lever via an expensive spindle drive. This adjusting lever is directly attached underneath an -2inner frame and is connected to a transverse tube and the lever arm via a welded structure. Any pivotal movement of an adjusting lever can only take place simultaneously on the pivot axis of the bed-base components, with the joints of said bed-base components having to endure considerable transverse forces due to the unfavourable lever actions. Consequently, implementation of this known adjustment device is very complicated, resource-intensive and cost-intensive.

Another device, known from US-A-4 225 988, comprises a mechanism for turning a person lying in a bed whereby via a shaft with handwheel extending underneath a longitudinal spar of a bed frame, a cable can be wound up which cable acts upon a lever mechanism, which is also situated directly underneath a pivotable lateral part and screwed to said pivotable lateral part. Such a device is not suitable for realising functional adjustment of back sections or foot sections, as is evident from the highly complex back or foot section adjustment in the same publication.

Furthermore, from US-A-1 658 776 a head and foot adjustment mechanism of a bed is known which is operated via chains, said chains also not being shortened but instead, via a spindle drive, moving cams on which braces extending upwards are arranged, said braces being connected with the head sections and foot sections so as to be articulated. This embodiment of an adjustable bed base too requires several expensive components and requires considerable production expenditure.

It is thus the object of the invention to provide a bed base which can be adjusted by means of an electric motor, said bed base being constructed from a small number of components and being simple and economical to produce.

This object is met by an adjustable bed base of the generic type stated in claim 1, which according to the invention comprises the features mentioned in the characterising portion of said claim.

Important advantages compared to known devices result in that the coupling element for each adjusting lever comprises a traction means which can be wound onto a shaft driven by the adjusting drive. The adjusting drive can for example be arranged so as to be fixed to the frame, on one of the longitudinal spars or transverse spars, without having to be pivotally mounted to compensate -3for an offset angle of a drive that moves a massive pull rod or push rod.

Furthermore, due to the absence of a drive shaft for the adjusting levers, there is also no torsional load of the drive shaft, with the diameter of the shaft being driven by the adjusting drive being so small that the traction means wound onto said shaft can only exert a very low torque on the shaft. This adjustable bed frame has a further advantage in that the traction means can easily be made to the required length so that the distance between the adjusting drive and the adjusting lever is freely selectable. At the same time, this construction according to the invention is very light in weight and does not require any expensive fittings for attachment to a frame. Consequently, this adjusting mechanism is very easy to retrofit to existing bed bases. To this effect, the shaft onto which the traction means is wound, can simply be adapted to the inside width of a bed frame, so that the construction according to the invention is completely independent of the width of a bed frame. In addition this construction is of very low design height so that the transport costs of the completed bed bases are significantly reduced when compared to other bed bases which are adjustable via an electric motor.

The construction is not limited to bed bases with slats, it can also be used in the case of bed bases with separate bed-base sections, for example those that comprise individual spring elements.

Further advantageous embodiments of the subject of the invention are provided from the further subordinate claims and in combination with further subordinate claims.

According to a particularly preferred embodiment of the subject of the invention, the adjusting drive is arranged on a longitudinal spar so as to be fixed to the frame, and the traction means is a simple webbing belt or braiding belt of high tensile strength. Spring steel bands or chain-shaped structures can also be used as traction means. Such a band can then directly and layer-by layer, be wound onto the shaft or onto a separate winding segment which winding segment additionally may comprise lateral guides, so as to form a roll. It is also advantageous if the adjusting drive can be arranged externally on a bed frame or a bed box, so that optimal placement becomes possible, irrespective of the construction of the bed.

-4- According to another advantageous embodiment of the subject of the invention, the traction means is a simple rope, wire rope or plastic rope of circular crosssection. Preferably a plastic-coated wire rope is used so that with the high flexibility the danger of injury from the plastic covered wire rope as well as wear and tear are minimised. Furthermore, this provides more even winding onto a section of the shaft which is designed as a winding device, said shaft being driven by the adjusting drive, with one end of the traction means being fixed to said winding device, with the wire being wound onto the shaft as it rotates. With an advantageous recess made so as to slightly deviate from the purely radial direction, for accommodating the end of a wire rope, the traction means is initially aligned on one side so that during winding, all subsequent windings are arranged one beside the other.

In a preferable embodiment, a winding segment of cylindrical shape is arranged on the shaft, said winding segment comprising a helical circular groove to accommodate the traction means so that the desired orderly manner of winding the wire rope onto the shaft or the winding segment is further supported.

Furthermore it is particularly important that the winding segments used for the various traction means can be of various outside diameters so that by exchanging them it becomes possible to simply and quickly vary the movement rate or the traction force without the need for any further changes to the adjusting drive. In this way the adjusting drive can be optimally matched to all existing sizes and dimensions of a large variety of bed bases.

In a particularly advantageous embodiment the drive comprises an electric motor arranged in a tube, similar to a roller shutter drive, with the traction means being wound onto said tube.

Preferably, the traction means acts upon the end of the lever arm which together with the adjusting lever forms a functional unit, in particular made in one part, with the line of influence of the force extending through the traction means and underneath the pivotal mount of the adjusting lever. Consequently, no laterally acting forces or moments are generated in the entire mechanism, which forces or moments could have a negative effect on the function and service life of said mechanism.

Also advantageous is an embodiment of the invention where the adjusting drive for pivoting a foot section or back section drives two shafts, either concurrently or individually and independently of each other, as desired, thus obviating the need for a second motor for pivoting a second frame part. To this effect, the adjusting drive comprises a respective coupling.

Below, one embodiment of the invention is described in more detail by means of drawings, as follows: Fig. 1 is a lateral view of part of an adjustable bed base; and Fig. 2 is a top view of part of an adjustable bed base.

The adjustable bed base comprises a frame 3 with two longitudinal spars 9 and two transverse spars 10 and at least one inner frame 2 configured as a pivotally mounted foot section or back section. On the frame 3 on a longitudinal spar an adjusting drive 1 driven by an electric motor, is arranged. Via a traction means 6, a lever arm 5 and an adjusting lever 4, said adjusting lever 4, below the inner frame 2 being attached to the longitudinal spar 10 so as to be articulated, and which adjusting lever 4 resting on the inner frame 2 underneath the lateral spar, said adjusting drive 1 driven by an electric motor makes it possible to pivot said inner frame 2, which is coupled to the longitudinal spar via a pivot axis 12, from a horizontal position to an upright position.

In this embodiment the adjusting drive 1 comprises an electric drive which, by way of a worm drive, drives a shaft 7 which extends across the width of the inner frame 2. On said shaft 7, in the region of the insides of the inner frame 2, a traction means 6 in the form of a webbing strap (Fig. 1) or a wire rope (Fig. 2) is attached, with the other end of the traction means 6 being attached to the lever arm 5 of the adjusting lever 4 so that as a result of rotation of the shaft 7 and winding of traction means 7, said adjusting lever 4 is moved on its pivot axis 11.

On a winding segment 13 which is situated on the shaft 7, the rope-shaped traction means 6 is wound in such a way that the windings are placed exactly one beside the other. To this effect the shaft 7 and/or the winding segment 13 comprise a radial drill hole which slightly deviates from vertical, with the angular deviation to normal approximately equating the lead angle of the wound-up windings. By contrast, strap-shaped traction means (not shown in the drawing) are wound up layer upon layer, forming a roll. For emergency-lowering of a r 6 raised part of the frame, the shaft 7 is disengaged from the adjusting drive 1, or the windir4 7 s segments 13 are disengaged from the shaft 7 so that the traction means can unwind freely.

By exchanging the winding segments 13, the pivoting speed or the raising force of the inner frame 2 can be varied in a simple way so that with one'adjusting drive a large variety of different inner frames 2 of foot sections or back sections of various designs can be adapted for being driven, without requiring any further intervention in their mechanisms. Similarly, the traction means 6 within the frame can be deflected via rollers or similar, to a further movable frame segment or to such a segment located further away.

Underneath an inner frame 2, an adjusting lever 4 is attached to the transverse spar 10 of a frame 3 via a pivot axis 11, with the tension means 6 preferablyextending underneath the pivot axis 12 and the adjusting lever 4 in a parallel or near parallel direction up to the shaft 7 so that no additional bending moments are generated in the components.

In this specification, except where the context requires otherwise, the words "comprise", "comprises", and "comprising" mean "include", "includes" and "including", respectively. That is, when the invention is described or defined as comprising specified features, various S. embodiments of the same invention may also include a f additional features.

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Claims

2. A bed base according to claim i, characterised in that the traction means is a flat strap.
3. A bed base according to claim i, characterised in that the traction means is a wire rope of circular cross section or another rope of circular cross-section. \\melbfiles\home\Leanne\Keep\12608-OO.doc 04/02/02 ii ei 8
4. A bed base according to claim i, characterised in that the adjusting drive is arranged on an associated bed base or a bed box.
5. A bed base according to claim i, characterised in that an electric motor arranged in a tube which is driven so as to rotate on its longitudinal axis, is provided as an adjusting drive.
6. A bed base according to claim 3, characterised in that a winding segment of cylindrical shape is arranged on the shaft, said winding segment in its cylindrical surface area comprising a helical circular groove for accommodating the traction means.
7. A bed base according to any one of the preceding claims, characterised in that the adjusting drive drives a shaft which extends across the interior width of the frame, said shaft being held in the region of the transverse spars; and in that one adjusting lever is made in one piece with a lever arm. 0o
8. A bed base according to claim 7, characterised in that the traction means is coupled at the end of the lever arm, extending underneath the lever arm and the pivot axis of the adjusting lever in a longitudinal direction which is approximately parallel to the direction of the longitudinal spars, with said traction means extending up to said shaft.
9. A bed base according to any one of the preceding claims, characterised in that an adjusting drive for pivoting two inner frames of a foot section and a back section, drives two shafts either concurrently or independently of each other, as desired. \\melb_files\home$\Leanne\Keep\12608-00.doc 04/02/02 21 9 A bed base according to any one of the preceding claims, characterised in that the adjusting drive is arranged in the frame at any desired distance from the adjusting lever and in that the traction means is made to a suitable length and is attached to the shaft or the winding segments.
11. An adjustable bed base, substantially as hereinbefore described with reference to the accompanying drawings. Dated this 4th day of February 2002 SIEGBERT HARTMANN 15 By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia *go \\melbfiles\home$\Leanne\Keep\12608-00.doc 04/02/02