EP1367975A1

EP1367975A1 - Adjustable bed

Info

Publication number: EP1367975A1
Application number: EP02703013A
Authority: EP
Inventors: Ulf Tolfsen; Michel S. Naert; Magnus Karemyr
Original assignee: Labyrint Development AS; Labyrint Dev AS; XDIN PUBL AB
Current assignee: Labyrint Development AS; Labyrint Dev AS; XDIN PUBL AB
Priority date: 2001-03-12
Filing date: 2002-03-06
Publication date: 2003-12-10
Also published as: SE0100843D0; WO2002074221A1; SE518670C2; SE0100843L

Abstract

Adjustable bed, comprising a frame with a central casing (10) arranged centrally under a mattress base, legs (24), and an adjustment mechanism. A telescopic leg arrangement (11) connects to at least one end of the central casing, in the longitudinal direction of the mattress base, and has an upper leg (22) articulated in the central casing for movement in the vertical direction, and a two-leg stand (24) which is telescopically displaceable in the upper leg (22) and, together with the upper leg, supports the central casing in a vertically adjustable manner.

Description

TITLE

ADJUSTABLE BED

TECHNICAL FIELD

The invention relates to adjustable beds, in particular to beds which are intended for institutional use, for example in hospitals and other nursing establishments.

PRIOR ART

A great many bed constructions which are adjustable are known. In the present context, the term adjustable is to be understood as meaning the possibility of changing the spatial position of, for example, a mattress base which supports a bed mattress. It may be necessary, for example, to set the height of the mattress base to a certain normal height. For beds used in institutions, it is also generally required that the bed can be stored away in a manner which takes up very little space, which is usually achieved by the fact that the supporting frame construction of the base of the bed can be adjusted from normal height to a reduced height which saves space.

Another type of adjustment which is sometimes required in connection with beds used in institutions is that the mattress base of the bed can be converted to give the user the possibility of a more or less upright seated position.

In addition to this, it is also often necessary for the mattress base to be able to be tilted about an axis extending in the transverse direction of the bed, and preferably also about its longitudinal axis. For example, French patent specification 2,257,264 discloses a bed whose height can be adjusted from a normal position to a loading position. It is additionally possible to tilt the base of the bed in order to set one end of the bed higher than its other end. Under the base of the bed there is a casing with an adjustment mechanism, and connected to each end of the casing there is a leg which can be set to different angle positions relative to the mattress base. Placed centrally under the casing, and fixed to it, there is a wheel arrangement which comprises wheel pairs arranged on both sides of the longitudinal axis of the bed. One of these wheels in each wheel pair is larger than the other, and there is a mechanism for shifting from the larger wheel to the smaller one. With the mattress base placed at normal height, the two larger wheels are used which, together with the two said legs, support the mattress base. In the tilted position, the large wheels are also used to support the mattress base together with said legs. The large wheels are retracted and the small wheels deployed when the mattress base is brought to its lowest position, after which these smaller wheels take over the function of the large wheels.

Swedish laid-open specification 466, 833 discloses a bed whose construction is built up around an underbody, a bed frame and two intermediate frames. The part called the bed frame, which serves as mattress base, is made up of a middle section, a head-end section and a foot-end section. These sections are articulated with each other so that, with the aid of the adjustment mechanism, the two end sections can be pivoted up and down in the vertical direction, i.e. about an axis transverse to the bed frame.

Another example of a bed with several frames, in this case an underbody and an upper frame, is found in published PCT application WO 94/27547. On the upper frame, which can be adjusted in height with vertically operating telescopic bars, there is a mattress base which is divided up into a number of mutually adjustable sections. Another example of a bed with the mattress base divided up into mutually adjustable sections is found in published PCT application WO 95/31171. Under the mattress base there is a mechanism for mutual positioning of said sections. The mattress base is supported by a stand with four legs which supports the mattress base at the corners of an imaginary rectangle. These legs are vertically oriented, and each leg is telescopically adjustable. By means of telescopic adjustment of the pair of legs at the head end or foot end, it is possible to raise or lower either end. In addition, adjustment of all the legs affords the possibility of setting the height of the bed.

A bed with an adjustment mechanism in a central casing under a mattress base is disclosed in the published European patent application bearing publication number 0,431 ,192. The mattress base is divided up into sections. With the head-end section raised, the middle section can be swung out horizontally from the bed, whereupon a seat is formed.

British patent specification 683,073 discloses a mattress base which is supported on an arched beam construction via an upper frame and which is divided up into a number of mutually adjustable sections. Separate extension pieces are provided for setting the height of the mattress base.

Some type of metal or metal-based material is generally used as material in beds of the adjustable type in question. However, other types of material have also been employed. An example of an adjustable bed made of plastic material, preferably reinforced plastic material, is disclosed in US patent specification 3,742,527. This bed too is made up of a number of individual frames for achieving adjustability.

All of the bed constructions mentioned above afford adjustment possibilities in one way or another. However, the ergonomic aspect is in most cases not taken fully into account. This applies in general to the examples of beds given above, particularly when these are to be used as beds in institutions.

The ergonomic aspect involves, inter alia, ease of use: for patient, for nursing personnel, for cleaning staff, for maintenance staff and storeroom staff.

The weight of the bed is important in this connection and should be kept to a minimum. Environmental aspects must also be taken into consideration. This involves environmentally friendly material, both for manufacture and for use.

OBJECT OF THE INVENTION

Starting from the abovementioned prior art and from the requirements which a bed of the type in question should be able to satisfy, the object of the present invention is to eliminate the shortcomings of the known beds and thereby make available an adjustable bed which is free of component parts making handling, cleaning, transport and storage difficult and which does not have nooks and recesses where dirt and colonies of bacteria can gather.

THE INVENTION

The abovementioned object of the invention is achieved with an adjustable bed according to the pre-characterizing clause of Patent Claim 1 , with the features which are set out in the characterizing clause of Claim 1.

The additional features which are included within the scope of the general problem mentioned above are set out in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a side view of an embodiment of an adjustable bed according to the invention,

Figure 2 shows the bed in Figure 1 seen from below,

Figure 3 shows the bed in Figure 1 seen from above,

Figure 4 shows the bed in Figure 1 seen from one end,

Figure 5 shows the bed in Figure 1 tilted in the longitudinal direction,

Figure 6 shows the bed in Figure 1 tilted in the transverse direction,

Figure 7 shows the bed in Figure 1 converted to a chair,

Figure 8 shows the bed in Figure 1 with the base of the bed lying horizontally at the maximum height in the vertical direction,

Figure 9 shows the bed in Figure 1 with the base of the bed lying horizontally at a reduced height in the vertical direction,

Figure 10 shows the bed in Figure 1 with the base of the bed lying at a further reduced height, corresponding to the loading height,

Figure 11 shows an embodiment of an adjustment mechanism with a drive device for the bed in Figure 1 , with the telescopic leg arrangement of the bed in a position corresponding to the loading position,

Figure 12 shows the adjustment mechanism and the drive device according to Figure 11 , with the telescopic leg arrangement of the bed in a position corresponding to the base of the bed placed at maximum height,

Figure 13 shows the head-end section of the bed in Figure 1 with associated adjustment mechanism and drive device, with the head-end section in the horizontal position,

Figure 14 shows the head-end section in Figure 13 in the raised position,

Figure 15 shows the foot-end section of the bed in Figure 1 with associated adjustment mechanism and drive device, with the foot-end section in the horizontal position, and

Figure 16 shows the foot-end section in Figure 15 in the lowered position.

The bed in Figure 1 has a supporting frame which, in the embodiment shown, comprises a central casing 10 which is placed substantially centrally under the bed in the longitudinal direction and transverse direction of the bed.

The central casing is relatively short compared with the length of the bed and is relatively narrow compared with the width of the bed.

In the embodiment of the bed shown, a telescopic leg arrangement 11 connects to each end of the central casing.

A mattress base, which in the illustrated embodiment comprises three sections, namely a middle section 12a, a head-end section 12b and a foot- end section 12c, is supported by the central casing 10. The middle section 12a of the mattress base has an extent in the longitudinal direction of the bed which substantially corresponds to the length of the central casing 10 and is supported by the central casing connected in an articulated manner at a hinge 15 in order to be able to execute a tilting movement about said hinge 15, i.e. about a central axis extending in the longitudinal direction of the mattress base.

The mattress base sections have the same width. The head-end section 12b is slightly longer than the foot-end section 12c, which in turn is slightly shorter than the middle section 12a. The head-end section is connected in an articulated manner to the middle section at a hinge 13 in order to be able to be pivoted upwards in the vertical direction, and the foot-end section is connected in an articulated manner to the middle section at a hinge 14 in order to be able to be pivoted downwards in the vertical direction. The adjustment mechanism and drive device for these upward and downward movements will be described later.

Along the outer sides of the mattress base sections extending in the longitudinal direction of the mattress base there are borders 12d, 12e and

12f, and in these there are openings 12g (Figure 7) for fixing side rails 16.

The openings 12g are designed and positioned in such a way that after the rails have been turned 90° out from the mattress base, said rails can be pushed inwards for storage under the mattress base. The middle section 12a of the mattress base, supported in a tillable manner, is held by the central casing 10 with sufficient clearance space to permit insertion of the central side rail too.

Bed end-pieces 17 are connected at the short ends of the mattress base. These bed end-pieces 17 can be pivoted outwards (Figure 7) and can be inserted under the mattress base by means of a pair of articulated and displaceable arms 18, 19.

In the embodiment of the bed shown in Figure 1 , telescope arrangements 11 are located at each short end of the central casing 10, and each of these is provided with castor wheels 20 which, in the embodiment shown, are in the form of a bogie arrangement which rests against the floor 21 on which the bed is placed.

Each telescope arrangement 11 has an upper leg 22 which is secured in an articulated manner to the central casing at a hinge 23 in order, by means of an adjustment mechanism and drive device, to be able to execute upward and downward movements in the vertical direction.

A two-leg stand 24 is arranged in a telescopically displaceable manner in the upper leg. By means of the adjustment mechanism and the drive device, this telescopic movement is coordinated with the movement of the upper leg about the hinge 23. As will be explained later, this coordinated movement takes place in such a way that the central casing 10 and thus the mattress base is lowered or raised without any great change in the distance between the wheels 20 of one stand and the wheels 20 of the other stand, i.e. the wheels are moved only slightly along the floor during adjustment of the height of the central casing 10 and thus of the bed.

The floor is therefore subjected to minimal wear.

The adjustment mechanisms and drive devices which have been mentioned in connection with the different adjustments are all housed in the central casing, the upper legs and the middle section 12a of the mattress base.

However, for adjusting the end section of the mattress base and for tilting in the transverse direction of the bed, certain smaller components required for this manoeuvring have to be deployed. On the whole, however, this means that the bed shown in Figure 1 basically has no externally exposed elements interfering with function, handling, hygiene, etc. An illustrative embodiment of an adjustment mechanism and drive device encapsulated in the central casing 10, the upper legs 22 and the middle section 12a of the mattress base will now be described.

Figure 11 is a diagrammatic view of part of a central casing 10, an upper leg 22, part of a two-leg stand 24, and, in outline, the adjustment mechanism and drive device used for placing the central casing and thus the mattress base at the desired height in the vertical direction.

At the bottom of the figure, the upper leg 22 has an external curvature which permits pivoting movement of the upper leg about the hinge 23 with good sealing against the central casing. The hinge 23 is placed at the outer end corner of the central casing in order to permit corresponding sealing. Inside the upper leg designed as a hollow body there is a bushing 25, and guided in the latter is the central shaft part 24a uniting the two-leg stand 24. A toothed ring 26 is provided on the upper leg 22 near to the hinge 23. Toothed wheels 27, 28 are supported in a rotatable manner by the central casing 10 and engage with each other in the manner shown in Figure 11. The toothed wheel 27 engages with the toothed ring 26. An arm 29 is connected in a rotationally fixed manner to the toothed wheel 28, and the free end of the arm is connected to the central shaft part 24a of the telescopic stand 24 by means of a push rod 30. At its ends, the push rod is secured in a rotatable manner to the arm 29 and the central shaft part 24a.

A linearly operating setting screw device 31 is secured in an articulated manner at one end to the upper leg 22 at an attachment point 32 situated at the lower end corner of the upper leg in Figure 11. In Figure 11, the adjustment mechanism is shown in the position it assumes when the upper leg 22 and the telescopic stand 24 have placed the central casing 10 in its lowest position (Figure 10). Encapsulated in the central casing 10 there is a drive motor (not shown) for driving the linear setting screw device 31. By activating the drive motor, the position of the setting device can be adjusted and with it the relative positions between the central casing 10, the upper leg 22 and the telescopic stand 24.

Figure 12 shows the linear setting device in the retracted position. During the movement to this retracted position, the toothed wheels 27, 28 and the toothed ring 26 have been rotated in the directions indicated by the arrows in Figure 11 , the arm 29 and the push rod 30 of the two-leg telescopic stand 24 having brought about movement to the position shown in Figure 12. In this position, the casing 10 and thus also the mattress base are at their highest positions in the vertical direction.

In the starting position in Figure 11 (bottom position), the angle α between the arm 29 and the push rod 30 is approximately 45° and at the highest position according to Figure 12 the angle β is approximately 90°. This angle relation has been found to be advantageous for obtaining the previously mentioned minimal change in the distance between the wheels of each telescopic arrangement 11 which bear against the floor.

With a mattress base of standard format and with the adjustment mechanism and drive device in the central casing 10 according to Figures 11 and 12, the telescopic arrangement 11 permits adjustment of the mattress base within a wide range. Figure 10 shows a lowest position in which the mattress base lies at hi = 300 mm from the floor and the central casing lies at only h₀ = 20 mm from the floor. Figure 8 shows a highest position h3 = 800 mm. In the intermediate position in Figure 9, h₂ = 600 mm. The distance between the wheel units 20 is largely the same in the different positions in Figures 8-10.

Figures 13 and 14 show the adjustment mechanism for the head-end part 12b of the mattress base. A setting screw device 33 is secured in an articulated manner to the central casing 10 at a hinge 34. The rod 35 of the setting device is arranged to be driven by a motor-driven gear wheel 36. The motor for this is, like the setting device, encapsulated in the central casing 10. A bracket 37 connected to the head-end section 12b of the mattress base is connected in an articulated manner to the rod 35 at a hinge 38.

With the adjustment mechanism in Figure 13 and the associated drive device, the head-end section can thus be adjusted to the desired position. Figure 14 shows the rod extended and the head-end section at a convenient angle for forming a comfortable backrest.

The only externally exposed openings required in the central casing 10 to obtain adjustment of the head-end section are on the one hand a narrow gap for the bracket 37 and on the other hand an opening for the rod 35. However, these apertures can be well sealed in relation to the respective part of the adjustment elements. The unexposed enclosure of most of the adjustment mechanism and drive device is not compromised.

Figures 15 and 16 show the adjustment mechanism for the foot-end section 12c of the mattress base. Since the construction in principle corresponds to the construction at the other end of the central casing 10, no further detailed description is required here. For corresponding construction elements, the same reference numbers have been used, but with the suffix c.

Tilting of the mattress base about its central axis 15 extending in the longitudinal direction of the mattress base is also achieved with the adjustment mechanism and drive device encapsulated in the central casing 10. The arrangement for this requires only one pair of lifting rods on both sides of the axis 15. If so required, passages for these can be sealed off in the same way as the passages in Figures 13-16. There is intended to be a gap between the mattress base and the central casing 10. This gap must not be so wide that the fingers can be introduced into it. By giving a suitable curvature to the middle section 12a of the mattress base and the central casing 10, the gap can have a constant minimal width during the entire tilting movement about the axis 15.

Figures 5-7 illustrate different setting possibilities. With the described arrangement it is possible to operate within the following angle ranges: 0 < i < 5°, 0 < α₂ < 10°, 0 < ₃ < 65°, 0 < α₄ < 70° and 0 < α₅ < 20°.

To derive optimum benefit from the advantages afforded by the bed construction described, the whole bed is preferably made of a reinforced plastic material, for example thermoplastic reinforced with glass or carbon fibres. Techniques for casting and injection-moulding of components made of such material are well established, for example within the automotive industry.

A great advantage afforded by such a technique is that it is relatively easy to give outwardly exposed surfaces a smooth design free from nooks and recesses. The individual elements, the central casing, the two-leg telescopic stand and the upper arm can be given an external design which provides the bed as a whole with an aesthetically pleasing appearance. It will be seen from the attached drawings that the underbody of the bed has, seen both from the side and from the bed ends, a gently curved, arc-shaped structure with smooth externally exposed surfaces.

Manufacturing the bed using plastic material which can be injection-moulded or cast gives degrees of freedom permitting incorporation of additional functions in the bed construction. For example, it is conceivable to design the sections of the mattress base with flow channels for air, for the purpose of controlling the temperature of the mattress base. As regards the manoeuvring of all the bed's adjustment mechanisms and drive devices, this is intended to be done either from a set of controls belonging to the bed or from a central monitoring station manned by nursing personnel.

The vital components of the adjustment mechanisms and of the drive devices can be gathered together in a compact box. This box can be designed in such a way that it can be plugged into the central casing in a simple manoeuvre, which further improves ease of handling for maintenance staff if repairs should be required.

Although a specific embodiment of the invention has been described, the inventive concept is intended to be limited only by what is set out in the attached patent claims.

Claims

PATENT CLAIMS

1. Bed, preferably permitting adjustment in all directions relevant to use and handling and permitting adjustment to a seat/reclining chair, comprising a mattress base, a central casing arranged centrally under the mattress base, legs, and an adjustment mechanism, characterized in that a telescopic leg arrangement (11) connects to at least one end of the central casing (10), in the longitudinal direction of the mattress base (12a-12c), said leg arrangement (11) comprising an upper leg (22) which is articulated in the central casing for movement in the vertical direction, and a two-leg stand (24) which is telescopically displaceable in this upper leg (22) and, together with the upper leg, supports the central casing in a vertically adjustable manner, and in that the adjustment mechanism comprises means (26-30) for said vertical adjustment.

2. Bed according to Claim 1 , characterized in that the adjustment mechanism and drive device for the latter are designed as a mechanism/drive device (26-32) encapsulated in said central casing (10), upper leg (22) and possibly mattress base (12a-12c).

3. Bed according to Claim 2, characterized in that the adjustment mechanism comprises means (23, 31 , 32) for modifying the angle between the longitudinal direction of the central casing (10) and the upper leg (22), and means (26-30) for modifying the effective length of the two-leg stand (24). . Bed according to Claim 3, characterized in that said means (23, 26- 32) for angle modification and length modification are designed in such a way that the distance between those ends of the two-leg stands (24) directed towards the floor remains substantially unchanged irrespective of the height of the mattress base above the floor (Figures 8-10).

5. Bed according to Claim 4, characterized in that said means (23, 26- 32) for angle modification and length modification are designed in such a way that the central casing (10) can be placed in the desired position relative to the floor (21) with a distance from the latter in a range of from a few centimetres up to the order of ca. 1 metre.

6. Bed according to one or more of the preceding claims, characterized in that the mattress base comprises a middle section (12a) which is supported by the central casing (10) and at each of whose ends there are end sections (12b, 12c) pivotable in the vertical direction.

7. Bed according to one or more of the preceding claims, characterized in that the adjustment mechanism also comprises means for tilting the mattress base (12a-12c) about its central longitudinal axis (15).

8. Bed according to one or more of the preceding claims, characterized in that the central casing (10), the two upper legs (22) and the two-arm stands (24), at the normal height and seen from the side, form a gently arc-shaped structure (Figure 1 ), in that corresponding gently arched structures (Figure 4) are found on the two-arm stands, and in that the arrangement as a whole has external smooth surfaces without nooks and recesses.

9. Bed according to one or more of the preceding claims, characterized in that the mattress base (12a-12c), the central casing (10), the telescopic leg arrangement (11 ), and other additional arrangements, for example bed ends (17), side flaps (16), etc., are all made of light, environmentally friendly and easy-to-clean material, preferably material of the thermoplastic composite type.